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Timing chain

Posted: Mon Dec 30, 2019 6:58 pm
by Sandun
Hi Friends

I saw , 2 type of Morris Minor timing chain , one of them two lines (double chain ), other one one line (single chain) - why like this ? What are the models they had use ? Please , i like to know it .

Regards
Sandun .

Re: Timing chain

Posted: Mon Dec 30, 2019 7:47 pm
by philthehill
The Morris Minor is fitted with the simplex timing chain (one row of links) and the tension is maintained by the two rubber rings.

The duplex timing chain (two rows of links) is kept in tension by the improved fit on the crankshaft and camshaft sprockets.

The duplex timing chain is usually fitted to those vehicles that have a greater loading on the valve train i.e. high lift camshaft and stronger valve springs for example the 1275cc MG Midget and classic Mini Cooper.

If replacing the timing chain I always recommend that the simplex timing chain is replaced by the duplex set up. A virtual straight fit and gives longer life to the timing chain, crankshaft and camshaft sprockets.

The twin rubber tensioners fitted to the simplex set up are not very efficient and soon loose their effectiveness allowing the chain to rattle after very few miles.

The best timing chain set up is the duplex fitted with the 'A' Plus chain tensioner as per photo below.
timing chain tensioner.jpg
timing chain tensioner.jpg (1.17 MiB) Viewed 7630 times
The above is a vernier adjustable version of the duplex set up with tensioner as used on my 1380cc comp engine.

Re: Timing chain

Posted: Mon Dec 30, 2019 8:25 pm
by ampwhu
absolutely. duplex is a great upgrade.

Re: Timing chain

Posted: Tue Dec 31, 2019 3:10 am
by Sandun
Thanks a lot

Re: Timing chain

Posted: Tue Dec 31, 2019 11:47 am
by pgp001
Phil

Can you offer any advice on how much tension to apply with the duplex setup, is it just a case of push the tensioner against the chain to remove any slack but not go any further, or does it need some pressure applying ?

I have the set of sprockets and chain that I got from you, and now have all the tensioner parts ready to fit as well as per your photo above.

Thanks
Phil

Re: Timing chain

Posted: Tue Dec 31, 2019 12:10 pm
by philthehill
I would suggest that the tensioner is set so that the bolt holding the tensioner is central in the slot of the tensioner.
If the tensioner is too hard to the chain the pad will wear quickly. Gentle pressure is all that is required to alleviate the slack. Any slack generated will be under the tensioner as that is the return side which incurs no loading.

Re: Timing chain

Posted: Tue Dec 31, 2019 12:26 pm
by pgp001
Thanks Phil

Re: Timing chain

Posted: Wed Oct 18, 2023 11:25 am
by rocco
Gents, I need some advice please. Again, yes I know. :tu1: :D

I want... no, make that need to buy a new timing chain kit with sprockets. The 948cc engine I have doesn't have tensioner and the chain does look a bit slack in the photo below. I don't want to mess about drilling or countersinking holes at the moment so a duplex kit is not required. I have to keep things as simple as I can at the moment.
Moggy_TimingChain.jpg
Moggy_TimingChain.jpg (476.37 KiB) Viewed 6810 times
ESM don't have any simplex kits in stock so I was wondering whether I could get one from a Mini parts supplier? If it comes with a tensioner could I just throw it away and use the rest of the kit? Can tensioners be retrofitted and is it worth it/easy to do? I can't figure out how a rubber ring around the back of the camshaft sprocket can keep a chain tight but I fully expect that I have misunderstood yet another thing about these motors.

I will be trying to gather up as many items as possible to bring back next month to get my engine running. I'm even going to try and the crankshaft removed so it can be measured and allow me to get the right bearings for it too.

Re: Timing chain

Posted: Wed Oct 18, 2023 12:15 pm
by philthehill
The simplex timing gears from a Mini can be fitted to a Minor but the simplex set up is designed to be used with a tensioner.
The two rubber rings of the minor cam gears does tension the timing chain but not for long as it looses its tensioning ability quite quickly.
If you do not want to drill any holes and not fit a tensioner just fit the two new rubber tensioning rings to your existing cam gear plus a new timing chain.
All other option require holes to be drilled.
Please use a correct spanner on the cam gear nut. Using a hammer and chisel will lead to a damaged front camshaft bearing.
I could not call myself an engine builder if I left a nut in that condition! :-( :-(
There is no need for all that sealant. Just clean the faces of the front plate and timing cover, grease the new gasket and fit the gasket and timing chain cover using the front pulley to centralise the timing chain cover to the crankshaft.
Fit a new seal to the timing chain cover. You appear to have the felt seal timing chain cover fitted. It is better to fit a later timing chain cover with lip seal and flat oil thrower.

Re: Timing chain

Posted: Wed Oct 18, 2023 2:32 pm
by les
That poor nut, it must have really annoyed someone, at least the washer keeps it company !! Don’t show us the rest of the engine :-?

Re: Timing chain

Posted: Wed Oct 18, 2023 2:37 pm
by rocco
Cheers Phil. Just to be clear, the photo is what I was presented with as I took the timing cover off. That nut is a mess but I didn't do it, honest guv.

I believe I'll need a new cam sprocket/gear because someone has taken a bite out of mine.
Moggy_CamGearDamage.jpg
Moggy_CamGearDamage.jpg (290.06 KiB) Viewed 6780 times
The timing cover looks like this. I cleaned it and painted the outside mainly to stop it rusting again. It should end up being gold. To me the seal in the cover looks like is rubber, not felt.
Moggy_TimingCover.jpg
Moggy_TimingCover.jpg (469.9 KiB) Viewed 6780 times
I'd also like to get a new crankshaft pulley because someone, not me, has had the mole grips on it instead of the puller.
Moggy_CrankshaftPulley.jpg
Moggy_CrankshaftPulley.jpg (369.76 KiB) Viewed 6780 times

Re: Timing chain

Posted: Wed Oct 18, 2023 2:40 pm
by rocco
les wrote: Wed Oct 18, 2023 2:32 pm That poor nut, it must have really annoyed someone, at least the washer keeps it company !! Don’t show us the rest of the engine :-?
Haha. Too late Les, I added a couple more photos before I saw your message. It's not had the best of treatment I have to admit.

Re: Timing chain

Posted: Wed Oct 18, 2023 3:18 pm
by philthehill
If you have a lip seal timing chain cover the oil thrower is wrong. It should be a flat plate (Pt No: 12A1148) not concave as per the above photo. The plate has 'F' stamped on its front face and the 'F' should face forward to the timing chain cover.
https://www.moss-europe.co.uk/oil-throw ... soc=137892
The timing chain cover with the seal fitted from the outside is a correct timing chain cover. BMC/BL made and fitted covers that had the seal being fitted from either the inside or outside.
The camshaft timing gear and the crankshaft pulley need to be replaced. Fit a later damped crankshaft pulley as the damped pulley allows the engine to run smoother.

Re: Timing chain

Posted: Thu Oct 19, 2023 8:31 pm
by kevin s
Another problem with the standard set up is the rubber rings disentigrate and end up as shreaded rubber in the sump potentialy blocking the oil pick up strainer then starving the whole engine of oil.

Re: Timing chain

Posted: Sat Oct 21, 2023 5:46 pm
by rocco
Being that ESM don't have any single kits at the moment and if only a couple of holes need countersinking on the front plate, I'm going to go for the duplex kit. It's cheaper too.

https://www.morrisminorspares.com/engin ... te-p830307

Re: Timing chain

Posted: Sat Oct 21, 2023 6:08 pm
by philthehill
Do not forget to fit the correct flat oil thrower plate marked 'F'.
The two holes should be countersunk to 82 degrees for UNF threads but a 90 degree countersink will suffice.
When drilling the holes in the front plate use a vacuum cleaner to catch any swarf.
Loctite the two countersink screws place.
These are the screws to use:-
http://www.minispares.com/product/Class ... o%20search

Re: Timing chain

Posted: Mon Oct 23, 2023 10:02 am
by rocco
Thanks Phil
Do the screws not come in the duplex kit? I've seen them in the image for the kit on some sites.
What impact will it have using the oil thrower I've already got? It's hard to understand how a flat metal ring can throw oil and perhaps that's why a concave one was used? I bow to your expertise here.

Re: Timing chain

Posted: Mon Oct 23, 2023 11:31 am
by philthehill
Some kits have the screws but using the Allen headed screws are best and I only use and recommend the best.
The flat oil thrower plate was designed for use with the lip seal cover. The concave oil thrower plate was designed to cover the felt seal which needed some oil to stay effective.
The flat seal throws the oil off its outer edge by the use of centrifugal force. The concave oil thrower plate does not really use centrifugal force to get rid of the oil.
Therefore I would recommend using the correct oil thrower plate for the timing chain cover and oil seal being used.