6 replies to this topic

[furiousd]

Hi All

 

I'm in the process of changing the verto clutch on my 1990 mainstream cooper 1275 (carbed engine).

 

I noticed the bolt that holds the clutch/flywheel to the crank wasn’t overly tight (not loose but not very tight) when taking it apart so want to make sure I do everything right this time around.

 

From reading this forum I’ve seen it recommended that the flywheel is lapped, is this a must or just an ideal thing to do? The reason I ask is that I’m not too sure on the process of lapping and I’ve already put the clutch and flywheel together, presumably the flywheel is put on the crank with the paste between the surface and moved around a bit? Also the engine is still in the car so not sure how easy this would be given the access?

 

I can see that I applied copper grease to the bolt which I’m now thinking is probably not going to help it stay tight, should I clean this off and should I apply (non permanent) thread lock?

 

As it stands I’ve torqued the bolt to the crank and has been left for a few days. I think my plan is to take the bolt out, clean the grease off with thinners, add thread lock torque it up again (leave for ½ an hour and recheck/re torque) then staking the lock tab and putting everything else back together.

 

Does this sound reasonable or should I be looking more into the process of lapping the flywheel?

 

The engine is mildly modified with kent 276 cam and stage 3 head if this makes a difference.

 

I’ve probably asked some silly questions so please be kind J

 

Many thanks

Chris

 

 

[Dusky]

A BL/ROVER apprentice once told me they aplied threadlockt ( loctite) to the big centr e bolt ( and ofcourse also to the pressur eplate bolts).

SO I would do it, can't harm.. :)

[Guess-Works.com]

With the engine in the car it can be difficult to lap the flywheel on, but is recommended, however, not essential...

 

I use loctite on the main crank bolt, 270 to be precise, this is a "don't come off unless you really want it to" loctite, Do not re-tighten once torqued as this will almost certainly break the already set(ting) loctite's grip.

[furiousd]

Thanks, this is pretty much what I wanted to hear!

 

I had wondered about retightening the bolt after applying threadlock breaking the seal. Given that its been torqued up for a few days now I think I will be happy to torque it again with the thread lock on once  and leave at that.

 

Presumably the copper grease does want cleaning off and should not have been put on 1st time around?

[Guess-Works.com]

Correct.

[AlexMozza]

What do you mean by lapping in a flywheel? Sorry to thread jack!

[Fast Ivan]

it refers to lapping the taper of the crank to the taper of the flywheel using an abrasive paste so that the mating faces are more accurately matched to each other, same process as lapping the valves/valve seats and ball joints