What's right valve gap for turbo engine?

[Jussi]

My engine sounds at cold like "lawn-mower", so there might be too much gap in valves (sound is like that). So what's the right gap and how you adjust gap, my mechanic thinks there are pieces (more to put to reduce gap). Usually (newer cars) you just "screw" the gap to be right. And what kind of job that is at totally, how much must take out to tune valves. If there are "adjustment-pieces", from what car are those?

Hope someone understand what I mean, not good technical-dictionary at hand right now.

[WayneB]

Jussi, your 910 Turbo sounds like a lawn mower? You must have some pretty hairy lawnmowers in Finland! The valve clearances (cold) are Inlet 0.13mm to 0.18mm (0.005mm to 0.007in) Exhaust 0.25mm to 0.31mm (0.010 to 0.012in) The clearances are adjusted with shims( thinner for more clearance ,thicker for less) The shims are located on top of the valve stems ,underneath the "bucket " cam followers. To access these you will have to pull the cam carriers! (and remove the belt etc) The carrier is also sealed to the head with special jointing compound made by Loctite( type 504) It costs $100 cdn a tube! As you can gather this is a big job( the manual has 10 pages (inc. illustrations devoted to it) I would wait for your manual to arrive before tackling it. I have found the shims are close to the ones used on Jaguar XJ40s Wayne

[Jussi]

Oops, that sounds what we afraid of

Yep, we have in Finland pretty raw lawn mowers

Ok we wait to get manual before to start this job (if we do it ourselves afterall ) Wonder where we can get those shims or can they make yourself (modified from something)?

[WayneB]

I wouldnt try to make them yourselves! The Jaguar XJ40 shims are the most common(over here) You might be able to swap some of the existing shims around to get the clearances you need. The existing shims can also be carefully made thinner by lapping them down on a stone.It sounds like you need wider ones though(as you are getting alot of noise) I also think the shims are the same as the old Hillman/Chrysler/ Talbot / Coventry Climax type ones(Imp) Wayne

[Splashout]

This is not that daunting of a job it is just verry verrrrrry verrrrrrrrrrry time consuming i think it is quoted at a 6hr job by the dealers. I did this while the engine was out which probably made it a lot easier as i had the cam housings on a bench. You then with fealer gauges measure the gaps you have and then note the difference to spec. Do this on both cams. You will probably find that some of the shims you can use on other valves. If you use a micrometr to measure them. Once you know what size shims you need you can then oreder them (see bellow) and put the new ones in making sure you measure all of them with a micrometer and then remeassure all your clerances. It took me about a day to do, but this was not spent solidly on this.

As for the shims them selves you should be able to order them from any dealer. I got mine from Christopher Neils over here

[scoule]

As Wayne mentioned, shims are certainly the same as Hillman Imp shims ... I think also cars like the TR7 used the same sizes.

I've done this in-situ before on my a Excel, not too bad a job - finding the permabond sealant took longer than anything else! One thing to be careful of is when measuring shims and clearances to calculate new sizes, beware that the valve stem hammers it's way into the shim and this can give a false reading on the clearance and the calculation could be out. Before ordering new shims, it may be advantageous to flip the shim over and re-measure so that the valve stem fits on the flat side of the shim ...

Typically the clearances close up, so I normally aim for the larger clearance of the specified range so that the next adjustment will be further away!

So far, the tin of new shims I found under the bonnet of a Hillman Imp in a scrapyard meant that I haven't had to buy any :-)

[WayneB]

Got rid of all my Imp shims years ago Has anyone found a good substitute for the Loctite 504 (permabond) for sealing the cam carriers? I found some stuff made by Permatex (Anerobic compound) but cannot find anyone who had used it on an Esprit . As the results of an oil leak from the cam carriers can be catastrophic , I went for the more expensive $100 alternative! Wayne

[Esprit Aviation]

Used Permatex "Right Stuff" gasket maker, as the old loctite leaked like a sieve after about 6 years(very hard and brittle). Did this as an experiment. Have approx 600 mi. on fresh build so not much history, but absolutely no leakage yet.

[WayneB]

I originally used that Permatex product (The right Stuff) when I did my belt/valve clearances, but before re-installing the engine I took it all apart(again) and re-sealed it with Loctite 504 as recommended by Lotus.

Glad to here yours isnt leaking though

[TurboEsprit1987]

The manual is a must have. I bought a CD ROM version on e-Bay. $89 USD and worth many times that.

Check your clearances. Then use a micrometer to measure the shims you presently have. Most of mine had no markings on them. Do the math and order the ones you need. They're only $1.80 each! I couldn't believe it. I paid $3.00 each for my VW shims back in 1980.

PS: That was at JAE.... no, this is not an infomercial.

- Nick

[Jussi]

Just bought that ServiceNotes book last year (it helped a lot). Still missing PartsList book, hoping to get it in this year.

[catty s2]

Just bought that ServiceNotes book last year (it helped a lot). Still missing PartsList book, hoping to get it in this year.

<{POST_SNAPBACK}>

Jussi

Check out item number 4605887756 on ebay for an Esprit service parts manual. Not sure if it covers your model but you can ask.

Dave.

[mchlrodrigues]

I originally used that Permatex product (The right Stuff) when I did my belt/valve clearances, but before re-installing the engine I took it all apart(again) and re-sealed it with Loctite 504 as recommended by Lotus.

Glad to here yours isnt leaking though

<{POST_SNAPBACK}>

You can use Loctite 504, 515, 518 or 509. They all should work fine. When Lotus started recommending 509 to seal the main bearing girdle instead of Wellseal, they told me I could use it on everything else (water pump and cam boxes) as well .

509 is only available in the US in big 300ml cartridges for $90.00 or so, and it will go bad after you unseal the cartridge. I haven't seen 504 in ages. Between 515 and 518, I'd suggest 518. 515 supposedly takes up 0.0005", and 518 "0" clearance. As far as 504 hardening up after six years, that seems like a pretty long valve adjustment interval to me - twice per decade. What's wrong with that?

[bladerunner]

mchlrodrigues

I was looking for Loctite 504 as recommended.

The local agent informed me that it was not available in S.A.

I got the contact number of the technical guy of Locktite and he said that the 518 product (available in a 50ml tube) will do the job on the cam carriers.

This product does not harden if two metal surfaces is not pressed together. Therefor it can not block oil channels and would wipe off on the outside. The excess on the inside would be "washed" away by the oil. (and won't clog the oil filter)

So Locktite 518 seems to be the right product. (As you pointed out)

Duncan

[molemot]

If using the Loctite silicone sealant, don't forget to allow for the thickness of the sealant when you do the sums. Last time I did mine, I used some trick pink stuff from SJ Sportscars, seems to work well and not contribute any measurable thickness. Don't think I'd turn the shims over, just measure the valve clearances and make sure you measure the true thickness of the shim by making sure your micrometer goes into the depression on the shim caused by the valve stem. You'll need the correct tool to undo the cam carrier bolts, they have star shaped heads - bought mine from Halfords, which has certainly gone upmarket as far as tools are concerned. If doing this job insitu, make sure you don't bend any valves by turning the engine or camshafts with the belt off - you can set the pistons to midstroke and turn the cams if you want, but make sure you get the timing right on reassembly. Also Don't Drop Anything Down The Oilways!!! tinkle tinkle splash and off with the sump......