MF 135 knocker

[Hawkes]

Ok, I have a 135 that leaked oil continuously out of the clutch bellhousing. Ran well, had it on the drier this year. Split it and renewed the rear crank rope seal and gasket. Whilst at it did the brakes, new rev counter cable, ign switch etc etc. I have just put it back together, fired it up, horrendous banging from the engine, sounds like a big end or a broken crank. Still has really good oil pressure so probably not a bearing? and it always starts well. I can't think of anything I could have done bolting it back together to cause this? I made a clutch alignment tool so it all went back ok with a bit of jiggling of pto and flywheel. Clutch is functioning and driveable.
I am going to have to split it again to investigate, any ideas?
And yes I have counted all my spanners!

 

[Daveh]

I'd loosen the injector pipes one at a time and see if the knocking stops, a duff injector can sound a lot like a big end.

 

[Mur Huwcun]

You can usually diagnose a brocken crank (although I’ve never heard of a 152 breaking one) by looking for endfloat on the front crank pulley or flywheel (remove clutch inspection plate, it’s quicker then starter unless it has a loader)

 

[startinghandle]

Did you tighten all backplate bolts?

 

[Hawkes]

just nipped down to workshop and tried a pry bar behind front pulley, maybe 10 to 15 thou end float so not much. Tried running it and slackening off each injector, it slows as expected but no difference to knocking. Then tried flat out, noise goes away but on low revs bang bang bang. Tried just turning over on key with fuel stop out and it knocks like anything. Tomorrow morning I think I will pull it all apart again for a look see. It is still chucking oil out of rear seal, which I renewed, so maybe it is crank trouble.

 

[startinghandle]

What oil are you using?

 

[Mur Huwcun]

It could also be sump gasket and not the rope seal, if it's going to be split then maybe drop sump anyhow

 

[fredf]

Has the balancer gone wrong in the sump I had one go years ago the engine run rough and vibrated but was not missing.

Tom

 

[MF-ANDY]

Has the balancer gone wrong in the sump I had one go years ago the engine run rough and vibrated but was not missing.

Tom

No balancer on a 3.152

 

[Mur Huwcun]

No balancer on a 3.152

Just the bolt on lump on crank IIRC?

 

[Daveh]

Probably a silly question but are you sure you tightened the bolts on the flywheel.

 

[MF-ANDY]

Just the bolt on lump on crank IIRC?

Yes true

 

[Hawkes]

I will investigate tomorrow and see what it is. Sounds like the sump needs to come off and check gasket anyway so I can see what is what.... I hope. Worse case is all apart and can't see anything wrong! How I hate that fuel tank mounting.

@Daveh now you have put that thought in my head it is a worrying one. It did get left for a day or two in the middle of the job and no tabs on bolts to remember tapping down........

@startinghandle Shell Rimula 15/40 I think, have used it for years.

 

[Daveh]

Sometimes things can get forgotten, especially when you are trying to do half a dozen jobs at once.
Few years ago i put the transmission back in a 3cx and forgot to tighten the bolts on the torque converter, that made a pretty awful noise when i started it.

 

[Hawkes]

Its confession time . @Daveh you were spot on! Loose bolts on flywheel, the perils of starting a job and leaving it for a day or two, then carrying on thinking I had tightened them. Having a crap memory doesn't help either.
So new bolts and tags picked up today ready for a second attempt.
Whilst I am back in there it doesn't look if oil is getting past the new crank seal I fitted so maybe as @Mur Huwcun suggested it is the sump gasket, is there another rope seal under the main bearing housing at the flywheel end that could be leaking, it is a pretty fast drip drip drip?

 

[MF-ANDY]

As @Mur Huwcun said it will be sump gaskets. These come in 4 pieces. 2 side gaskets that dont leak and 2 cork strips that curve around the front and rear housings. These go hard and leak. Are you sure you didn't catch the bottom rope seal housing gasket when you fitted it. Did you fit the 2 parts of the housing in the right places. The top and bottom are different. The bottom one has a slot to allow oil to drain back to the sump

 

[fredf]

No balancer on a 3.152

Sorry I was thinking about a MF 290 that I had the teeth on one of the gears striped.

Tom

 

[startinghandle]

I have a dexta which stopped leaking from the rear seal when I put Fuchs
HDX 30 oil in engine

 

[Hawkes]

As @Mur Huwcun said it will be sump gaskets. These come in 4 pieces. 2 side gaskets that dont leak and 2 cork strips that curve around the front and rear housings. These go hard and leak. Are you sure you didn't catch the bottom rope seal housing gasket when you fitted it. Did you fit the 2 parts of the housing in the right places. The top and bottom are different. The bottom one has a slot to allow oil to drain back to the sump

Thanks for that info, the sump corks sounds very likely. I put the crank rope seal housing on the way it came off with a new gasket, but I will check it is the right way up now I am back in there! It could well have been put on upside down before, but it doesn't appear to be leaking from there.

 

[startinghandle]

Is engine breather clear ?
Is radiator core blocked? Even a dust coating will act as insulation preventing heat getting out
Is fan blade clean?