11 replies to this topic

[dan187]

Model: 1275 sprite
Year: 1992
Description of problem (please be as in depth as possible):

I had an oil leak out of the clutch to block seal (causing the clutch to slip) and a low compression in the third cylinder, so decided to take the engine out and sort all this.

Whilst the engine was out i gave it a good clean and replaced all the gaskets and seals.

I found that the low compression was due to a stuck piston ring which had formed a groove in the piston and damaged it. So i replaced all the pistons with a new set which have a slightly higher compression ratio, and i had the bores honed because they were a bit worn.

I also put a new clutch plate and diaphragm (and thrust bearing) in.

got the car back together and started running it.

I have two problems, firstly the engine seems to have a lot of vibration in it and rumbles a lot when it revs, the spark plugs are black when i look at them.
I'm sure that the timing is pretty close and firing in the right sequence and the fuelling is ok.

Secondly i'm having trouble engaging 1st, 2nd and reverse when the engine is running (reverse grinds) and there is rattling from the thrust bearing or other component in the bell housing.

Any help much appreciated,
could the CR be too high?
is it possible to have the flywheel on wonkey?
is it just my timing setup?
It seems to have a fair bit of power tho because i have driven it round a little.

All was working fine (other than slippy clutch) before i took it apart

Any non-standard parts that might be involved with the problem? Head has already been skimmed

[bmcecosse]

Need to know more - what did you do with the bearings ? Regrind crank - or just new shells ? Are you sure the big end are back on the correct rods (and right way round) - and in the same bores they came from ? Dd you double check the flywheel is seated correctly - and is the plate in right way round ?

[dan187]

Thanks for reply,

I didn't remove the crank so that should be fine. I stamped the con rods (1-4) so i knew which order and which way round (stamp faced front of engine). no new shells.

How should i have checked that the flywheel was seated? The clutch plate? can't it only go in one way? (it's verto)

[Pauly]

Did you replace the flywheel? Is it verto/pre-verto if pre-verto was it all balenced?

Paul.

[bmcecosse]

I would say a mistake to not fit new shells - but ok at least we know the crank was not disturbed - and the caps are back where they came from. I assume the engine was free and easy to turn by hand after assembly ? Yes - normally the plate can only go in one way - but it 'may' be possible to put in wrong way round - dunno - never tried it! The vibration and noise from the thrust bearing etc does perhaps suggest a problem in the flywheel area - may be as well to have the cover off and inspect everything - making sure the flywheel is correctly mounted and the big bolt is TIGHT!

[eden7842]

engaging gears is defiantly to do with your clutch. id get a new one personally

[dan187]

verto clutch, same flywheel as came out. not balanced.

Yeah engine turned easy, a little stiff to begin with but i put that down to the new rings and honing.

I will take the cover off and have a look.

[Pauly]

Clutch release bearings do rattle, ive never heard a release bearing not rattling on a verto set up to be honest.

Paul.

[Boomboy77]

Rumble could be plug leads on wrong, 2 cylinders swapped over?!?!?! Would explain the black on the plugs as its not firing under compression.

Gear crunching is because you havent set the clutch up correctly. I found the technique in the haynes book of lies needs to be done 2 or 3 times before its happy. Make sure theres no air in the clutch fluid too.

[dan187]

Gear crunching is because you havent set the clutch up correctly. I found the technique in the haynes book of lies needs to be done 2 or 3 times before its happy. Make sure theres no air in the clutch fluid too.

cheacked air in clutch, its a verto clutch, what do i need to set up other than throw out stop? if backed that all the way off to make sure i wasn't restricting travel.

Thanks
Dan

Edited by dan187, 06 July 2009 - 07:50 PM.

[bmcecosse]

There's rattling - and there's RATTLING ! Better have a look - because of the vibration!!

[dan187]

I have taken the cover off the housing. the flywheel/ clutch assy is not on square. How can it not be with a taper shaft? tried refitting but still goes on wonkey