New the register. Mk2 g60

[Tsanchez13]

Having a problem with my 89 rocco. Bought it in bad shape. Has dual webbers 40s n a cam not sure which size. Just had a compression test done and 3 cylinders under 8 psi. The original problem is it woult not idle. The care still can go when it needs but will not idle. Has anyone encountered the same issue. I am new to vw and do not have much time with en.

[scrappy1382]

8psi ???? you sure ?
taken from another site

According to the Bentley guide (section 15.4) the compression on the G60 (PG) engine should be between 116-174psi when new with a permissible difference between all for cylinders of 43.5psi and a wear limit of 87psi.

[steve bain]

do you mean 8bar? that would be 116psi which would be within tolerance. doubt it would run at all at 8psi!

[unknownmale]

Must mean 8bar, which is still low. I would suggest your idling issue is much more likely to do with the twin weber set up than compression.

But you'd need to provide more information about what the car is doing while idling.

If it's wandering around up and down the rev range, in my experience this is caused by vacuum leaks or dirty jets.

If it's idling too high, check the idle screw, turn it all the way out. or perhaps you have your mixture too rich, choke on or any combination of those points.

If it dies without idling at all then perhaps the engine is running far too lean, again, could be a vacuum leak, could have your mixture turned all the way in.

Does it do this when warm, cold or both?

you mentioned G60 in the title, Are you sure you have a G60? can't say i've seen a G60 on webers before.

I reckon if you can provide a bit more information and perhaps a couple of images of the engine bay you'll get the right answer on here.

[Tsanchez13]

Sorry it took so long took get bacj just got back from vacation. I have some pics attatched to help. The mechanic wh looked at it said he thinks it the block. Confirmed it is not a g60 its just a 1.8. L 8v. My main questuon is since it will not idle and my compressin are as followed.
1-8 bars
2-7.5 bars
3-6.5bars
4-7bars
I was also told the engine is burning oil when warm. Just looking for advice on which direction to do

[Tsanchez13]

The car dosnt idle thats the problem. As soon as i turn it on it sits at about 1000 rpm for a sec then just dies out. When it warms up it will stay on for a sec longer but then cuts out. The throttle is not lagging when i give it gas it still get going pretty quick. I have a single weber set up im thinking about putting on and seeing if it does any difference.

[unknownmale]

Compression is low. But it could be valve stem seals.

An easy way to find the low compression would be to do a dry compression test (Remove all plugs) followed by a wet compression test (Add a small amount of oil into the cylinder before running the test) If the compression increases with the oil in the cylinder then it's likely you have worn piston rings. If compression does not increase then it's likely the issue is with the head.

If you or your mechanic have the equipment then the best way to determine the reason for the low compression would be to perform a leak down test. Basically pumping compressed air (With smoke is better) and then tracking where that air is going.

What's the mileage on the engine?

[Tsanchez13]

167k on the motor. Im thinking about doing an engine swap but thats a whole different thing. Trying tk figure what will be cheapest and create most power. Do you think it could have anything to do with the dual webbers

[unknownmale]

I'm fairly sure the issue with your idle is down to the carbs not being correctly set up as they are difficult to work with. But the compression on your motor is low, so it's worth figuring that out.

If you want power then you'll never get it from a 1.8 carb even with cams. Best off converting to a KR, ABF, 1.8t 20v etc. Plenty of guides and info on forums about these. Worth noting too that the mk2 scirocco shares the same chasis (A1) with the mk1 golf, jetta and caddy. So any conversions you see for those will be the same.

[Tsanchez13]

Thanks for all the advice. Going to do the compression checks and see what happens.

[Tsanchez13]

Better news i guess. I adjusted the idle speed screw for both of the webbers and it idles now a little higher but not dying atleast. Its there a specific way i need to have the adjustment screws all set up

[unknownmale]

You'll have to play around with it to get it running right. I would suggest first adjusting the fuel mixture until the car sounds like it's running at it's best, then move to the idle speed, then ignition timing, back to idle speed, 2000rpm, fine tune timing. Back and forth until everything is right.

I'm no expert though, i'm sure there is someone on here with more experience of the twin weber set up.

[james butler]

first you need to sort out your engine issues as you wont be able to do any fine carb tuning if the mechanicals in your engine arent up to scratch.
it would be worth calling someone in to diagnose what exactly is the problem then go from there especially as tuning multiple carbs is a speciality and easily gotten wrong.