Compression test results - Bruce's

What, you compressed Bruce?

They look good. Are you having any problems?

On or around Tue, 02 Dec 2003 18:13:42 +0000, Nikki enlightened us thusly:

bloody sight better than mine was the other day, and I bet it's worse now.

I had 5 at 8.5-9 bar, 1 at 7.2, 1 at 6 and 1 at 5. bar*14 = psi, so mine were 125 or so for the good uns, and down around 70 for the worst one.

Still running though, a week later, although I think only on about 6 cylinders now.

I sincerely hope that the car will be fixed today, so I can take the landy off the road and fix it.

On or around Tue, 02 Dec 2003 18:13:42 +0000, Nikki enlightened us thusly:

sorry, didn't answer the question, did I?

book says 9 bar minimum, IIRC, or about 125 psi, so there's nowt wrong with them at all.

Relative consistency is what you are after - and you have it, it seems. If this is the motor with the missfire, at least you have probably eliminated piston / ring / valve problems. Which leaves you back with the cam, plug leads, dizzy cap etc.

Best of luck - Mike.

Noisy timing chain and the garage we took it to because it was running rich said we had a cylinder failure on No 7.

So much for the computer test results which indicated cylinder 7 was failing.

Not really noticed a misfire - was running rich and a sod to start. Its had new rotor arm, leads, distributor and 2 sets of plugs in the last year, the last set only changed about 500 miles ago. They were black again when we tested the compression the other day. Timing chain and cam we haven't done yet. We thought we might need a transplant engine after being told that cylinder 7 was failing on the computer diagnosis when we took it up to get the problem sorted where it was running rich.

Alex

Well, it sounds like its STILL running rich!

Thoughts: 7 & 8 are the "usual culprits" IF it IS the cam. What about temp senders? I know nothing about the EFi system but I do know that most (?) vehicles take engine temp as a pointer to weaken mixture after start once the engine is warm.

Mike.

H'mm what was that thingy that keeps sticking on efi's...like summat to do with a stepper motor or sumat, usually fixed with a clean and wd40.....nope..give up....

but on a more helpful side I can recommend Gunsons Colourtune (colortune for those on the dark side) you can see quickly if it's rich and it's cheap.

I can also recommend there gas analyser at about £65 it's been used lots with Percy , Morph and Jlo.

Lee D

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Mmmmm... time to take it elsewhere then. More likely just a dodgy plug or plug lead on pot 7, I'd have said. Try swapping the plug and lead to a different cylinder.

Cheers Gary

i.e. you've eliminated most of the expensive bits.

Cheers Gary

They look fine, Nikki. Nice and consistent across the pots. No 8. might be starting to wear or it could just be that the guage hadn't sealed quite right. Still not far enough off to worry about though.

Cheers Gary

On or around Wed, 03 Dec 2003 14:32:48 +0000, Alex enlightened us thusly:

f*ck off. 14's handy, it's times 7 and times 2, and it's close enough for jazz or land rovers.

The test they carried out was a "power balance" test. The computer cuts each cylinder out in turn and measures the drop in engine speed. If no.7 "failed" it just means there was little or no drop in engine speed for that cylinder. Comp test shows no mechanical faults so must be ignition side.

HTH

Says 15 on the back of the Gunson thing Bruce bought to test compression.

The needle hasn't moved on the Disco for a few months now and its one of the things I have actually moaned at him about to do, but he hasn't done yet. I'll tell him when he gets in.

Or running the engine in the dark to see if any discharge is visible...

Plenty of spare dark at this time of year.