17 replies to this topic

[dphx42]

Hi All

 

Hope someone can help me.

 

Recent work:

New clutch kit installed 

Exhaust was blowing this was fixed.

 

Engine was running ok before work done.

 

Symptoms:

RPM goes up when the clutch is depressed.

Car refuses to idle below 1500 rpm

When driving car runs at about 2000rpm

When running without choke rpm drops and engine cuts out.

Before a carb retune idle would sometimes go from 2000rpm down to 200rpm then recover back up.

 

Things i have tried:

Replaced Spark plugs. no change.

Tried re-tuning carb still wont allow me to drop revs below 1500rpm without spluttering.

Needle in carb piston feels like it is on a spring is this normal?

 

I have checked the vacum advance pipe and also checked dizzy that the base plate moves.

 

Things done before clutch installed:

New leads, New rotor arm, new condensor. New dizzy cap.

 

Car: 1989 998cc with HS4 with waxstat jet.

 

Thanks

 

[Ethel]

Pressing the clutch relieves the engine of the task of spinning the transfer gears so maybe they're your problem. Odd that they could get tighter without some clue like nasty noises though.

 

An alternative could be something catching on the clutch that clears when it's depressed - engine mounting bolt?

[Nick Warwick]

Could be a possible air leak on the inlet manifold since the exhaust leak was fixed (guessing you had a new gasket?)

 

Also how much did you turn the adjustment screw on the carb?

[dphx42]

Ethel:

2 flywheel pullers where broken trying to remove the clutch. The engine mounts were changed as well they took ages to get back on.  Could that be it?

 

 

Nick:

I was told the exhaust was blowing at the manifold clamp so i dont think ive had a new gasket.

 

I have had to open the jet down/clockwise a lot to get it stable at high revs.

I have found if i restrict air to the carb a bit using my hand then the revs go up.

[Ethel]

It might be an engine tune issue as Nick suggests, but it would be a very sickly engine that can't even cope with turning the tranny gears, and that would be noticeable with or without the clutch in.

 

Did you use the original engine mounting bolts with their full compliment of washers? Though I think you'd need more than a few missing washers to cause that problem.

[dphx42]

Sorry dont know about the bolts work was carried out by someone else.

[KernowCooper]

If you restrict the air intake and the engine revs up the mixtures weak and drawing air somewhere, with it running spray wd40 around the manifold and see if it revs up pinpointing the leak

[dphx42]

I tried the wd40 and ive now developed a whistle.

 

Also I have managed to get the idle down to about 1500.

 

Engine is still splutering and im still getting a small kangaroo at low speeds.

 

I think i need to have the compression and timing checked and have it tuned at a rolling road / garage.

[cal844]

You have an air leak,try tightening the manifold studs(engine cold!) If that fails to stop the leak change the gasket

Edited by cal844, 26 January 2015 - 10:41 AM.

[KernowCooper]

Sounds like a inlet manifold leak if you did the wd40 test and got a whistle noise

[dphx42]

Im going to replace the carb gaskets aswell.

 

Whats the best way of changing the manifold gasket?

 

Will i need to lower the exhaust after removing th carb?

[KernowCooper]

Single pipe system with clamp, you may just have enough room to remove the manifold, if not undo the front pipe clamp to diff bracket

[dphx42]

Thanks KernowCooper ill try that this weekend coming.

[mk3 Cooper S]

Tighten the manifold nuts from the inside working outwards when you replace the gasket.

 

Have you got a top engine steady fitted?

[dphx42]

Update:

 

Ive now replaced the manifold gasket and the manifold nuts.

 

Ran a compression test : Cyl 1 (155psi) Cyl 2(155psi) Cyl 3(165psi) Cyl 4(155psi)

 

No whistle but still having a lumpy / mild kangaroo at low speeds.

 

Only things ive not done are contacts & timing (i dont have a timing gun yet!)