TLR Engine Reassembly

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keychange
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TLR Engine Reassembly

Postby keychange » Thu Jun 14, 2012 2:21 pm

Hi

I have completely disassembled my TLR 200 engine and am now in process of reassembly. I have done top end rebuilds on multi-cylinder 4stroke engines before but never split the cases so this is new territory for me and I ask your forbearance if some of my questions appear silly but I would appreciate any constructive comments.

    I have a full gasket set - should I supplement the gaskets (not head) with a smear of silicon
    I am replacing the mainshaft and counter shaft bearings however the replacement bearings are sealed whereas original are open balls - should I remove the seals in order to allow the oil to do its work or leave them sealed



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Re: TLR Engine Reassembly

Postby TriCub » Thu Jun 14, 2012 2:39 pm

Keep the silicon away from any joint unless there is no gasket to start with and then only use a good quality product like "3Bond" white or grey. I have seen engines destroyed with beads of silicon cloging oil galleries.

Yes remove the rubber seals to let the oil flow through. There is normaly grease in the bearings under the seals that I remove as well, it can contaminate your clutch plates if let into the oil.



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Re: TLR Engine Reassembly

Postby FM350 » Thu Jun 14, 2012 4:53 pm

Never ever use silicon on a TLR motor...........the only joint that needs compound is the cam bearing housing which fits on top of the head, and something like Yamabond is the best stuff to use here. Genuine shim type head gasket is a good idea, as are genuine valve guide seals, as the cheap pattern parts are nowhere near as good as OE Honda.



keychange
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Re: TLR Engine Reassembly

Postby keychange » Sun Jul 01, 2012 5:15 pm

I have reassembled and started the engine but something is wrong - a knocking noise originating somewhere around the flywheel (using screw driver stethoscope). The engine turns smoothly by hand. I removed the flywheel and sorry about the lousy picture but you might be able to see something obvious. I can't for the life of me figure out how the tensioner works - and my manual really shows little details. I would imagine the collar would take up the slack but I can't see how it does so - the tensioner arm looks to be too loose so maybe I have the spring incorrectly installed. It may be something else entirely but this was one area that I was not sure of and the noise is coming from this vicinity

Image



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Re: TLR Engine Reassembly

Postby FM350 » Sun Jul 01, 2012 7:09 pm

Your pic looks like it has been taken by a phone, so isnt good enough to be able to see much detail. The tensioner spring can only be fitted in one way, and you will find a parts book will provide a line drawing which will show exactly how its meant to be fitted.

I would suggest checking whether or not the cam chain is loose before anything else, and if it is then loosen the 14mm tensioner nut on top of th cases, and see if the tensioner arm moves upward to take up the slack.

If it doesnt then its very likely the tensioner rod which fits inside the part with the 14mm nut, will be marked or damaged in some way, and this will need to be removed and any damage or marked areas smoothed out so the rod moves freely.

Damage to the tensioner rod is caused by over tightening the 14mm adjuster nut, which means the tensioner wont move, and I would guess is the cause of many cam chains being needlessly replaced, purely and simply due to tensioner not working.



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Re: TLR Engine Reassembly

Postby TriCub » Sun Jul 01, 2012 10:46 pm

keychange wrote:I have reassembled and started the engine but something is wrong - a knocking noise originating somewhere around the flywheel (using screw driver stethoscope). The engine turns smoothly by hand. I removed the flywheel and sorry about the lousy picture but you might be able to see something obvious. I can't for the life of me figure out how the tensioner works - and my manual really shows little details. I would imagine the collar would take up the slack but I can't see how it does so - the tensioner arm looks to be too loose so maybe I have the spring incorrectly installed. It may be something else entirely but this was one area that I was not sure of and the noise is coming from this vicinity

Image

The tensioner works by that spring loaded arm pushing it upwards but only when the nut on top of the crankcase is undone this in turn let the tensioner blade bow forwards to tighten the chain. While this nut is loose turn the motor slightly forward(counter clock) to keep the front side of the chain tight. You should see the plunger move upwards, after this re-tighten the nut. Also check that the spring loaded arm is free to move, if it is not fitted correctly with the correct washers and sleeves it can jam when the 10mm headed bolt is done up.

Hope this helps.



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Re: TLR Engine Reassembly

Postby FM350 » Sun Jul 01, 2012 11:19 pm

The correct way to adjust the cam chain on a TLR is to let the motor tick over, loosen the 14mm adjuster nut very slightly, then carefully nip it up taking care not to overtighten. In general knocking noises from TLR cam drive area are related to wear in the head itself where the cam runs, and the noise comes from the cam moving about in the worn bearing area, and this often seems to result in knocking noises. Very easy to check, as you only need to remove the cam sprocket cover and carefully check for any sort of play. If there is any at all, then this will need to be sorted out, as the problem will only get worse as time goes on.



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Re: TLR Engine Reassembly

Postby keychange » Mon Jul 02, 2012 10:11 am

Thanks TriCub - that does help a lot, now that I know how it is supposed to do its job. There is no contact at the moment between the arm and the tensioner and while the arm moves it doesn't appear to push up. I know the spring is correctly fitted on the arm but I may not have anchored it correctly on the inside - that will be my first job.

As for the head FM350 there was no indication of knocking when listening through the screw driver - all the noise is around the flywheel.



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Re: TLR Engine Reassembly

Postby TriCub » Mon Jul 02, 2012 11:03 am

keychange wrote:Thanks TriCub - that does help a lot, now that I know how it is supposed to do its job. There is no contact at the moment between the arm and the tensioner and while the arm moves it doesn't appear to push up. I know the spring is correctly fitted on the arm but I may not have anchored it correctly on the inside - that will be my first job.

As for the head FM350 there was no indication of knocking when listening through the screw driver - all the noise is around the flywheel.


If the arm is not contacting the tensioner rod there is definetly something wrong with the spring fitment. There isn't much else in those motors that can cause a noise in that area especially is it was quiet before the rebuild. (Except for main bearings and big ends)
If it was me I would not undo that tensioner nut while the motor is running as the cam can whip back and forth at low speed. I have heard of motors that this method was used on that now have bent valves due to the chain jumping teeth, their tensioner spring may have been a bit week. You need to the front part of the chain tight and then let the spring do it's job to tension the chain.
I just had a look at manual for the TLR and it does say to adjust the tension with the motor idling, I would still do it static if it was me.



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Re: TLR Engine Reassembly

Postby FM350 » Mon Jul 02, 2012 3:55 pm

Interesting that Honda seem to have got things wrong regarding adjusting cam chains on the TLR? Seriously though anyone adjusting cam chain on one of these bikes using the alternative (and incorrect) method suggested here may well find they have cam chain noise. Reason for this is if there is a tight spot in the chain and this is in contact with the tensioner blade when a static adjustment is made, the chain will then be loose when the motor rotates. This is always the case to some extent and these motors are always a little noisy from the cam drive area when first started after a rebuild, until the chain is properly tensioned.

To check for cam drive problems on these bikes, first adjust the chain properly as Honda suggest, then if there is any noise, remove cam sprocket cover and check chain tension, as well as for any possible play in cam bearing. If there is any cam bearing play, head must be removed to rectify this. If chain is loose the problem relates to either the chain itself or the tensioner mechanism. Chain should be renewed to eliminate any possible problems here. If bike has been completely stripped and rebuilt then check the tensioner mechanism has been properly assembled using line drawings from Honda parts book. If cam drive was noisy previously, check that cam tensioner rod is free to move in tensioner housing, and if not strip this and resolve the problem areas.




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