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        General >> Problems >> RH chain tensioner modification
        
(Message started by: Tobbe on Feb 21^st, 2005, 3:58pm)

Title: RH chain tensioner modification
Post by Tobbe on Feb 21^st, 2005, 3:58pm

As known a lot of 24v cosworths have problems with the RH chain tensioner. I am about to replace mine, and I was thinking about modifying the old one. My idea was to make a O-ring groove just right outside of the lube hole on the piston/plunger and test with an o-ring if it will make any differ, all though I haven't dissambled the old on yet so I don't really know what the problem(s) with it is, maybe it's a non-return valve failure on it. Perheps the best would be to make a new sleeve and a new plunger but harden it more. Since I've got the equipment to manufactor them it could be worth a try. It is really crap when they don't even last for 120000km.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 22^nd, 2005, 9:14pm

Just a little update on the subject

I did replace the RH tensioner tonight, and as I suspected the sleeve and the plunger had excessive wear. I guess they are not hardened enough. The one-way valve works fine on it.

Going to make a cold start of the engine tomorrow (about -15c) and I am hoping the rattle will be gone.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Baz on Feb 23^rd, 2005, 8:07am

-15c? Where are you Tobbe.....Antarctica?

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 23^rd, 2005, 10:08am

Actually I am in the middle of Sweden by the coast, and it have been much warmer this winter then usuall. It's normally -25 or colder this time a year.

Anyway, I made a cold start up at -12 and there were still some chain rattle, not as much as before but it was there, next step i to replace LH tensioner.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 23^rd, 2005, 5:51pm

Checked the hardiness of the plunger today, it's only
35-36 HRC. Going to manufactor a new sleeve and plunger and harden them to about 55-60HRC then there should be no problem with wear after a few thousands of miles. And a set of washers to compensate for the age of the tensioner spring are also to be manufactured.

If anyone got a LH tensioner dismounted and are willing to make a few measurments of it for me I would really appreciate it. I need the following measures:

Total length of the sleeve (removed from housing)
Total length of the plunger

I asume theese are the only measures that differ from the RH tensioner.

As thx I might be able to get you a set of both RH and LH side. (Sleeve+o-ring, plunger and washers). I.e if I get the hardening right.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 23^rd, 2005, 6:18pm

In addition:

It was not possible to modify the rh tensioner with an O-ring groove and an o-ring,due to that there would not be enought of material left to ensure the plunger not to break into 2 pieces caused by fatique. On the modified ones the lube holes will be moved back a bit to increase the sealing area.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 25^th, 2005, 11:22am

A little update:

Manufactured a few test peices in SS1672, going to harden them tonight with various temperatures. The sealingness (hope that word excists in english) between plunger and sleeve is much better then new original parts. Will get some pictures later on and test results of the hardiness and demolitiontests.

Still need the measuerments of the LH tensioner.. Maybe I just have to remove mine and use that one.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Scorpioen84 on Feb 25^th, 2005, 1:26pm

Tjenare Tobbe...

Bra at det er flere skandinaviere her...
Så mye rart me disse engelskmennene... Hehe...
Blir ensom som eneste Normann å Skandivavier her...
Håper du lykkes med prosjektet..

Måtte temperaturen vare... God helg.!

Title: Re: RH chain tensioner modification
Post by Eddie on Feb 25^th, 2005, 4:32pm

Hope your not talking about us! ;)

eddie

Title: Re: RH chain tensioner modification
Post by low_tom on Feb 25^th, 2005, 6:25pm

i think..
i thought i was the only scandanavian here,
with all these englishmen
now there are norge and scandananvians.
hope you like my project.

;)

Title: Re: RH chain tensioner modification
Post by Eddie on Feb 26^th, 2005, 5:29am

Very amusing,I just noticed the addy at the top of this thread!

eddie

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 26^th, 2005, 6:37pm

Did some hardening today, I think it was a success but I can't be sure I got 55HRC until I am back at work and can measure the surface hardiness, but I think it got really hard and I also need to make a demolition test. The measurements of the plunger and sleeve changed a bit, so the plunger has to be grinded to right size according to sleeve after hardening but that's no problem.

Test pieces.....
http://groups.msn.com/_Secure/0VgANA1kbM!KPQ8KrzBdX3KZd7PEpnYhAt7zI8hc070yrtkgT2aWoawiw8hIUZjLjoRY!lNO7dP*AngMMjp2V1lv6HNbXhw2NwJZ50pkzpPDZwf5R4MxSFbI3Tml8QKmY/plungerandsleeve.jpg?dc=4675511844716178808

Theese pieces are just for hardening tests.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 26^th, 2005, 6:40pm

Hmmm. It got big, to big, didn't it!?

Title: Re: RH chain tensioner modification
Post by scorpio_man on Feb 26^th, 2005, 7:00pm

hi there

just a bit!!!!!!!!! ;D ;D ;D

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 27^th, 2005, 10:00am

There must be one that have one of theese but for the LH side in their garage:

http://hem.bredband.net/tobhed/tensioner.jpg

I still need to know the length of the LH tensioners plunger and sleeve, I was hopeing to have one ready before the next weekend so I can try it on my cossie..

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 27^th, 2005, 8:15pm

Got some drawings of the RH plunger and sleeve.

http://hem.bredband.net/tobhed/plungerdrawing.jpg

http://hem.bredband.net/tobhed/sleevedrawing.jpg

If the surface treatment is a success, they will be manufactured tomorrow, at least the begining of it.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 28^th, 2005, 8:54pm

Did test the surface hardiness today, it was a failure, only 28HRC, but I did find out what went wrong, I got SS2172 or 2143 instead of SS1672. Harden a new piece today in SS1672 and it seems to be hard enough. So tomorrow I will see the result when measure it and make a demolition test. Maybe I got a finnished RH tensioner plunger & sleeve that I can test by the end of this week.

If this little project is to no interrest for you cosworth owners, let me know. Got to wonder becuase there's no comments about it.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Paul B on Feb 28^th, 2005, 9:05pm

I'm reading it all but I have to be honest, its completely over my head I'm afraid ??? ::) :-/

Title: Re: RH chain tensioner modification
Post by waders on Feb 28^th, 2005, 9:08pm

on 02/28/05 at 20:54:31, Tobbe wrote:

If this little project is to no interrest for you cosworth owners, let me know. Got to wonder becuase there's no comments about it.

//Tobbe

Tobbe, I don't have a Cossy but I'm still interested in your project ;D keep posting ;)

8) ;D 8) ;D 8)

Title: Re: RH chain tensioner modification
Post by SaveTheNight on Feb 28^th, 2005, 9:09pm

sorry Tobbe .. well I for one am watching with interest .. just not sure whether the hardness has any relation to the problem .. as often a new tensioner does not cure the problem .. as you probably know , I too am working on the chain problem in general ..so i'm interested to see what result you get .. in our own research we tend to put at least 8-10k miles on before stripping down ..so it's a bit of a drawn out procedure ... regards ..... STN

Title: Re: RH chain tensioner modification
Post by Tobbe on Feb 28^th, 2005, 9:37pm

More of my theoris about this problem.

The chain gets extended when it get wear, so the tensioner needs to extend more then it was design to, also the spring get's to short (N/mm not enough pressure from it).

The right thing would probably be to replace the chain.

But in my plunger the lube hole is moved back so you will still have it sealed, and there will also be washers to improve the pressure from the spring. The big question is how much extended does the chain get.

An other experince
We are converting my cousins BMW 635 with a turbo, we were modifying the compressioratio down to 8:0 and to do that we had calculated that if we increased the combustion chamber height by 2,73mm we would get it right, so we manufactured a steelplate (in the exact shape of the cylinderheadgasket), but we were not able to have this height becuse the chain got to short, the funny thing is that with no plate we had a lot of lose chain.

What I mean is that a little wear on the chain might cause a quite big extention for the tensioner and it might loose oil due to the lube hole is to close to the side and it's not thight enough. And if the non-return valve is working propertly there is no need for the tensioner to loose so much oil, even though you don't might actually have pressure there when you start the engine, you got oil there and when the chain is pressing against the plunger it should not move backwards, and if the spring is doing it job, the weight of the loose chain would not be able to press the plunger back even if you will loose oil between plunger and sleeve.

Will make plunger and sleeves in various length and test them.

//Tobbe

Title: Re: RH chain tensioner modification
Post by gaz01gaz on Feb 28^th, 2005, 9:47pm

hi tobbe,i can assure you my friend we are all reading with great interest,keep up the good work and keep us informed of any developments and progress, ;)gaz

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 1^st, 2005, 11:08am

Got the hardening sorted out now, the test peice was 46 HRC and that's hard enough. The diameter decreased by 0,02mm on a solid shaft. Know what I need to start making the RH tensioner. There will be three different ones, 1pcs just as the original but tighter, 1pcs 4mm longer and one pcs 9mm longer.

Hope this will do the trick.

//Tobbe

Title: Re: RH chain tensioner modification
Post by howiedintheplace on Mar 1^st, 2005, 7:27pm

Wow at last the one real issue with the Cossie V6 engine getting some real head stratching going.
Yes Tobbe keep it up, your doing some great work & making some good improvements.

The way I see it is there is some issues with a number of things in the timming chain department.
1. The guides tend to break up or over heat.
2. The tensioners loose pressure over night causing the famous early morning rattle & wear problems.
3. Some cases of the cam cogs wearing & the chain's actually jumping teeth.

Yeap the chains stretch but only break when something else fails?

So if the guides where made more hard wearing, the tensioner's pretty much as Tobbe described. Slightly harder, tighter, longer & perhaps the cam cogs need to be harder as well, would that be a better set up than standard? It would certainly be in the correct direction I think.
Hope to do some work on this myself soon.

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 1^st, 2005, 7:53pm

I am considering to mount pressure guagers at both RH and LH tensioner to be able to get some readings to be able to determant if I need to replace LH with a modified one or not and also to be able to actually measure some results after the modification and compare it with the original ones. On the RH side I have a brand new tensioner, LH side it has done 120000km.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Scorpioen84 on Mar 2^nd, 2005, 1:07pm

Why isnt it enough to change the hole lot, chain, tensioners and all that, with orginal ford (crap).
Will it last as long as the once on now.?

Where is the fuelfilter on the 2.0scorp.?

Tobbe, only 200kmt.? I did 189kmt in my 2.0 down the sweedish roads... (Arvidssjaur to østersund..)

The main roads in sweeden is so strait and good you can drive topspeed ewerywhere...
(xept for the reindeers and elgs and foxes and and and... hehe...
What is the 2,9`s topspeed..?

Title: Re: RH chain tensioner modification
Post by october on Mar 2^nd, 2005, 5:25pm

hi scorpionen84.fuel filter should be located on the n/s rear of car in front of fuel tank.you will need a 8mm (could be a 7mm :-/)spanner /socket to loosen clamp around filter,or to remove bracket altogether a 13mm socket.pipes are quick release type fittings.hth

Title: Re: RH chain tensioner modification
Post by Rubbersmoke on Mar 2^nd, 2005, 8:54pm

Hi Scorpioen84

I have did 245 kmt with my 2,9 -24v ;D
Kjell,

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 2^nd, 2005, 9:22pm

Then you did travell in about 226km/h, there is a 11% dismatch between the speedometer and the actually speed.

Guys, please try to stick to the real issue in this thread, the start up rattle problem.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Scorpioen84 on Mar 3^rd, 2005, 10:28am

hehe, sorry... ::)

i did ask a topich q. but now awnsers... ;)

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 3^rd, 2005, 5:11pm

Got a special mill/cutter manufactured today so it is possible to mill the front of the plunger into the right dimensions, as shown on the drawing there is a taper with a radius in the bottom.
Soon there will be a plunger and a sleeve.

Will test them with oil at a pressure of approx 4 bars for 24h and see if they will leak. If not they will be hardened and tested again. And then there will be a demolition test in order to see how they break. And if that will not be satisfactory there will be a change to another steal. And if it is satisfactory there will be a live test in my car.......

//Tobbe

Title: Re: RH chain tensioner modification
Post by Dave on Mar 3^rd, 2005, 8:03pm

Tobbe,

this is all really interesting stuff, it is great that you are using your knowledge and equipment to get a possible solution to the timing chain rattle issue. At the moment we are having up to -5 degrees C around here, nowhere near your temperatures, but the chain in my car (1996 24v) certainly rattles at that temperature!

Good luck, and keep posting! :)

Title: Re: RH chain tensioner modification
Post by VladSoare on Mar 4^th, 2005, 9:44am

Tobbe, I'm also very interested in this matter.
I hope your experiment succeeds and you solve this rattle problem once and for all.
Don't give up! :)

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 4^th, 2005, 11:55pm

Found this info on the scorpio web site
http://hem.bredband.net/tobhed/cylhead.jpg

I guess this is becuse the length of the chain will get to long other wise.

Compared to the BMW b30/m35 engine, you can take it down alot more, but then BMW got a much longer tensioner.

http://hem.bredband.net/tobhed/bmw.jpg

This is what I think:
As long as there is no rattle from the chain and everything sounds ok, there is no risk for it to snap. And if the start up rattle is eliminated, there's no need for guides to break, unless the angle against the gear will be to deep.

//Tobbe

Title: Re: RH chain tensioner modification
Post by SaveTheNight on Mar 5^th, 2005, 8:56am

Hi Tobbe .. the chain length does not have a great bearing on the head tolerance reasons .. mainly it's because the Cosworth head is already taken close to it's safe limits < although one can skim slightly more than suggested without damage> .. but that measurement has to be maintained to prevent the valves hitting the pistons either in normal running or possily with valve bounce or abuse .. regards ..STN

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 5^th, 2005, 9:09am

Are the valves really going that close in TDC? 0,13mm?

Talked to an industrial dealer the other day, they got chains that fits but they didn't want te sell any if they were to be used for camshaftdrive, they couldn't garantee that the chain wouldn't snap, but they did have better prices then FMD got. And if you got a splitted chain you could easily mount it, and then just rivet it toghether with a special tool. This would save a lot of work and money, i.e if the guides and the sprockets aren't damaged. There must be a chain with better quality then fords to be found somewhere.

//Tobbe

Title: Re: RH chain tensioner modification
Post by low_tom on Mar 5^th, 2005, 9:52am

excue me if i'm wrong or missed something,but when i used to work on bike engines we used to skim the top of the block in preference to the head. Would this not be a case where you could apply that?

Title: Re: RH chain tensioner modification
Post by howiedintheplace on Mar 5^th, 2005, 12:51pm

Tobbe
I think the 2 main problems are the guides & the tensioners. If you dismantle an engine which shows no sign of chain rattle you still find the guides either damaged or in bits, so there has got tobe a problem there & the tensioners well we all know about them.
Chains seem O.K so would not worry about them, at £75 each I think they are not that over priced, how much do you pay?
SaveTheNight is working on the guides problem, if you keep looking at the tensioner's you will I am sure together both come up with improvments on the old designs.
If you need any pics, measurements let me know.

Title: Re: RH chain tensioner modification
Post by johnv on Mar 5^th, 2005, 2:13pm

does any one know the price of a brand new cosworth engine, rather than a re-conditioned one, just in case i ever need one.

Title: Re: RH chain tensioner modification
Post by SaveTheNight on Mar 5^th, 2005, 5:53pm

John ... seven grand was the figure a while back ... BUT .. a customer of ours recently had a quote from a Ford dealer of around four < I resume they were quoted incorrectly but one never knows !! > ... STN

Title: Re: RH chain tensioner modification
Post by colinw on Mar 5^th, 2005, 6:16pm

Im no expert in this field but in my unfortunate experience the chain is not the problem but the tensioners etc my chain which had done around 140k had not stretched or snapped but when the tensioner broke up it allowed the chain to jump a cog or two with horrendous results ,we probably could have got away with using the old chain but in the general scheme of things the cost of a new seemed pretty fair

Title: Re: RH chain tensioner modification
Post by John_Carmon on Mar 5^th, 2005, 6:19pm

This is facinating reading, keep up the good work. I had to change the timing chain etc. my 24v about 12mths. ago, mechanic said I had gotten by on a wing & a prayer, as all guides etc. where lying in bits in the bottom, & cogs & chains were well worn. Mechanic said this was a design fault by ford, as parts were not upto the job. It cost me £1200 to put all right.

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 6^th, 2005, 8:47am

The FMD here in sweden wants 125£ each for the chains... And 123£ for the tensioner. So only in order to buy the parts to be able to replace chains, tensioners, gudies and gaskets will cost atleast 1200£.
I bought my RH tensioners from fordparts UK, and I saved almost 34£ and this includes fast shipment to Sweden.

//Tobbe

Title: Re: RH chain tensioner modification
Post by johnv on Mar 7^th, 2005, 5:07pm

Thanks to Savethenight. £7000 just to bad but £4000 is more respectable.
The reason I ask was that if you can't do the work yourself and the sheer cost of the repairs, it might be best to cut your losses and go for a brand new engine.
Yes, I know it should not be necessary, but if faced with the cost of spending a large amount and then something else needing more money thrown at it in about a year time better go the whole way, and at least that will be ok for years to come.

Title: Re: RH chain tensioner modification
Post by howiedintheplace on Mar 7^th, 2005, 7:14pm

New engine? Well there is some bargains if you keep your eyes open. I missed one for £500 last year but yesterday I picked one up for £110 & that is not a typo (£110). It's what is called a basic engine. A complete bottom end, complete timming chains etc & complete heads except for the rocker covers.
It's brand new & has never been fitted to a car.

Some great bargains if you look.

Sorry to crash your post Tobbe

Title: Re: RH chain tensioner modification
Post by johnv on Mar 7^th, 2005, 8:08pm

hi howdy places.
you just made my day. not that i need a new engine but it nice to know what the costs are.
My Cosworth is going great at the moment. I got posh petrol in it and its loaded with catoclean.
They don't like going very slow around town, like the exhaust sounds like when I pull the plug out the bath. Gugel, gugel, gugel.

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 7^th, 2005, 9:01pm

Steve, thanks for the measurements for LHS plunger and sleeve. I'll send you a set to the RHS and LHS when they are finnished, I'll let you know when.

Got the RHS machined tonight. Got some testing to do tomorrow before they are to be hardened.

//Tobbe

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 8^th, 2005, 7:09pm

The picture shows a modified sleeve and plunger
http://hem.bredband.net/tobhed/sleevetensioner.jpg

The demolition test of a hardened one didn't go to well.

I have talked to a company that harden metals and they could do the hardening propertly. I can't get the right temperature for all the treatments step with the method I use.

Maybe I can find someone that have a owen to burn cheramics in, it would work.

//Tobbe

Title: Re: RH chain tensioner modification
Post by VladSoare on Mar 22^nd, 2005, 6:20am

Tobbe? Any news?

Title: Re: RH chain tensioner modification
Post by Tobbe on Mar 22^nd, 2005, 7:20pm

Still working on the hardening problem, talked to a hardening specalist and they might be able to do the job for a fair price depending on if they were to do another hardening job with the same metal.. At the moment I am putting my time into another more urgent project. Got to get the BMW Turbo started before the summer.

I'll make a post when I make progress with the tensioner. If I could sattle for 27HRC then I can make them easy but maybe that's not hard enough for the surface. But they are not brittle then.

I can harden them to 48 HRC but they get a bit to brittle then, maybe the right thing is to pay up the money in order to get the hardening job done propertly... And then the surface could get up to 61 HRC and i the core won't be brittle.

//Tobbe

Title: Re: RH chain tensioner modification
Post by howiedintheplace on Mar 23^rd, 2005, 12:27am

Tobbe
I would be interested in buying a pair off you if it helps with your costs. PM me with details.

Title: Re: RH chain tensioner modification
Post by shionogi247 on Apr 3^rd, 2005, 3:25pm

Hi Guys,

It's very interesting what Tobbe is doing!!! I have been thinking about the RHS chain tensioner a lot, and have tried to think of various solutions. Somewehere else on the Scorpio Site is the story of Vlad Soare who bought an pre-lubing system for his engine (see www.autoenginelube.com). This system is very simple but useful: during operation of the engine, some oil is trapped in a storage tank. When shutting off the engine, a valve closes and the oil in the tank is trapped there under pressure. Before a new start is made, you turn the carkey to position I and the valve opens, thus releasing the oil from the tank into the engie. This way the engine is pre-lubed (lubed before starting it) and this also applies to the RHS chain tensioner. The rattle should be gone when installing this system, and Vlad states it works perfectly. So, I ordered this system from www.enginelube.com and got it some two weeks ago. When installing the system, a connection has to be made from the engine to the oil tank, and this is done by removing the oil-pressure sensor and replacing it by a T-piece. On one end, the sensor is mounted and on the other end, a hose is mounted which leads to the oil tank. However, Vlad stated that this was a bit of a problem, because the pressure sensor is somewhere underneath the engine and it's very tight in there. So I thougt of another solution: why not connect the oil tank directly to the RHS chain tensioner? There is a hexagonal bolt to the top of the tensioner, and a hose could be fitted here. This week I am going to visit a hydraulics specialist to see if a suitable hose can be made, and I will keep you guys informed. I will send some photo's too. The main problem with the RHS chain tensioner is loss of oil when the car is parked overnight, especially in cold nights. My Cosworth has done 200.000+ kilometers and the rattle won't get worse, but it gives me the shivers every time I start the car ...

Title: Re: RH chain tensioner modification
Post by Tobbe on Apr 3^rd, 2005, 4:58pm

The prelube sounds very interresting, the plug is 1/8 npt I think. Maybe I too will try something like that..... Keep us updated..

//Tobbe

Title: Re: RH chain tensioner modification
Post by VladSoare on Apr 4^th, 2005, 9:13am

The system still works perfectly (in fact it's so simple that hardly anything can fail). I did make a minor modification, though. I didn't like that the soleniod opened on ignition, so I mounted a switch on the dashboard. This way it opens only when I want it to. After starting the engine I turn off the switch, which guarantees that pressure in the tank will be maximized.
When the solenoid is closed, oil cannot exit the tank. However, oil can still enter the tank if the outside pressure is higher than the inside pressure. What I mean is that the solenoid behaves like a one-way valve when it's not energized. So if the solenoid is not energized, every time the engine revving speed increases (which means every time the oil pressure increases) some oil enters the tank and stays there.
Without this switch, the solenoid is energized all the time while the ignition is on, so even if oil enters the tank at high revs, it flows back at low revs.

At first I thought there were some problems with this kit, but it turned down it was all due to my not understanding its principles well enough. Now it works fine and it really helps keep the rattle under control.
But I'm still going to replace the entire timing gear when I have enough money. After reading that the chain guides are made of plastic and can fail any time, with or without any start-up rattle, I'm not feeling very safe. :-/

Title: Re: RH chain tensioner modification
Post by shionogi247 on Apr 15^th, 2005, 9:10pm

Hi guys,

I am still waiting for the guy who would make a direct connection from the oil storage tank to the chain tensioner... I'll keep you posted ... Tobbe, how are things going, is your tensioner ready yet?

Greetings

Title: Re: RH chain tensioner modification
Post by Tobbe on Apr 15^th, 2005, 9:33pm

Well, still got this hardening problem... Unfortunely. Have starded to work on a cheap pre-lube system, with an simple control system so it will do one purge of oil when the pressure in the resovoir is higher then 0.5 bars and the igniton is switched on, in order to get another purge the ignition has to be swithed off and on and the pressure needs to be higher then 0.5 bars.... The tank is in anodized and coloured aluminium so it will look real nice.. Will post some pictures when ready.

I'll keep you updated on how the pre-lube proceeds and if it is a success. Will still work on the hardening problem... Just need the right tool and then it will work.

//Tobbe

Title: Re: RH chain tensioner modification
Post by shionogi247 on Apr 19^th, 2005, 12:36pm

Just spoke to my hydraulics man, he''ll have everything ready by tomorrow!

When I get everything back, I'll try to post a picture here...

Hans

Title: Re: RH chain tensioner modification
Post by shionogi247 on Apr 27^th, 2005, 8:14pm

Hi everyone,

Last Saturday I got everything back from the hydraulics guy, and finally I was ready to install te pre-lube system onto the Rh side chain tensioner. The system can be seen in the picture showing the chain tensioner, the oil tank and the connecting hose. I also added a detailed view of the connection of the hose to the tensioner. Notice that the original blanking plug at the top of the tensioner is unscrewed and then replaced by the screw which holds the hose in place. PAY ATTENTION: the blanking plug goes in only 4 mm and that's for a reason: inside there's a tiny oil channel which must not be blocked! So the screw which holds the hose shouldn't be screwed in too deep! Tobbe, if you're designing your own system be aware of this!

Well, it took a lot of work to get to the chain tensioner because it's impossible to do anything from above the engine bay. There's not enough room to use a spanner or any other tool, so I was left with no other option but to work from underneath the car. I had to remove the undershield, alternator (dynamo/generator), and the bracket that holds the alternator and steering pump. This was about two hours of wrok, and it took me and my fahter another hour to put it all back together. The result can be seen in the third picture I added. The tensoner can be seen with the hose attached. The hose leads to the tank which is mounted in the left corner of the engine bay (seen from the front of the engine) in this case it's a left hand drive which means the oil tank is mounted at the battery side.

Well, then I became rather nervously, would it work? I didn't attach any electric connection to the tank because first the tank would have to be filled with oil. In order to achieve this, I started the engine ... and the sart-up rattle was there but it didn't go away! The engine rattled for about a minute and then I couldn't bear it any longer si I stopped the engine. The rattle continued of course because the oil was flowing to the tank and not to the chain tensioner! However, at some point the tank had to be filled all the way and oil pressure had to build up in the tensioner, so I started another time and yes, the rattle semd to dissapear.

I then measured the pressure inside the oil tank, it was about 6 bar which is rather high I think. I started the engine again and took the car for a test drive. I noticed that the tensoner chain could be heard at low revs, so I didn't like the result of my modification.

I drove the car for about two hours to see if the ratlle would dissappear but no, it was still there. Furthermore, a valve seemed to ratlle as well so I was afraid I ruined the engine somehow.

So, on Sunday, I took everything out which cost me about two hours, and I then reinstalled the original blanking plug onto the chain tenioner. Thank God everything went back to normal then, slight starup rattle and after that ... just the smooth silence of a fine engine running ... pfew, no harm done after all ...

So, my conclusion, don't mess with the chain tensioner, any alteration seems to lead to a low pressure at low revs and the result is a contiunuous rattle, even if it's very silent...

So what will I do next ... well, there's no other choice but to fit the system just like Vlad Soare did ... Vlad, do you have pics of the system you installed??

Greetings

Hans[img][/img]

Title: Re: RH chain tensioner modification
Post by shionogi247 on Apr 27^th, 2005, 8:21pm

How do I post pics here?????

http://C:\Documents and Settings\jgvanek\MyDocuments\My Pictures\PICT0019

Title: Re: RH chain tensioner modification
Post by SaveTheNight on Apr 27^th, 2005, 9:08pm

Hi Shionogi .. we have used pre-lube systems on race engines for many years and there are hundreds of versions .. mostly quite cheap .. here is an explanation link you may want to look at .. : http://www.autoenginelube.com/pages/903474/index.htm

I'm not sure which one Vlad used but remember that you are also " disguising " possible faults and there can be consequences . .. the oil t-piece at the oil switch connection and tubing also need to be fail safe as any failure in there will do far more damage and quickly ... there's no real substitute for curing the initial problem .. expensive as that may be .. cheers now ........ STN

Title: Re: RH chain tensioner modification
Post by VladSoare on Apr 28^th, 2005, 6:51am

I used the same system, from AutoEngineLube.com.
I remember taking a few pictures at that time, but I don't know if I still have them. I'll try to find and send them to you.

It works very well (with the slight modification I wrote about above) and keeps the rattle under control, but I'm not entirely satisfied. Even if I don't hear the rattle any more, only God knows in what condition the chain guides might be. They might break at any moment, without any warning. That's why I want to replace the timing chains, guides, tensioners and anything else I can before it's too late.

Title: Re: RH chain tensioner modification
Post by des on Apr 29^th, 2005, 7:19pm

current price of the kit is $189.00 dollars +$41.00 ish shipping roughly £130.00 a cheap
alternative to a total chain rebuild if you have low miles will see what customs want by the end of the week its on its way.................

Title: Re: RH chain tensioner modification
Post by Tobbe on May 14^th, 2005, 3:00pm

Finally I am getting somewhere with the hardening, got one test bit hardened to 49,8 HRC, and it's not brittle. Soon there will be a tensioner ready for a live test on my car.

Title: Re: RH chain tensioner modification
Post by Eddie on May 14^th, 2005, 4:26pm

Were all running out of fingernails here! :D

Eddie