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ENGINE OUT COUPLE OF QUESTIONS
https://www.ausmini.com/forums/viewtopic.php?f=2&t=61929		 Page 1 of 2
Author:  jester99 [ Sun Mar 21, 2010 8:51 pm ]
Post subject:  ENGINE OUT COUPLE OF QUESTIONS
8)

Engine out this afternoon, couple of quick questions?

Is 1" of play in the timing chain good?

Should i upgrade to a double row?

will i need to modify the timing chain cover to clear the chain? i notice my cover does not have anything there to modify? as in the part i have read that you need to remove is not on the cover i have.

i am sure the massive wear in the timing chain may be contributing to my tuning issues.




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the origonal reason for removing the engine was to repair the miriad of oil leaks but the list has grown to be quite large now that the engine is out.

the front seal was the worst leak of all of them. as you can see the previous owner had a love for silicon sealant and has made love to the entire engine with it, in many places no gasket is used at all, just silicon! :lol:
Author:  TheMiniMan [ Sun Mar 21, 2010 8:59 pm ]
Post subject: 
That sort of play/wear in a single row assy is quite normal,,, i was almost going to say--> "That`s not much for one of those" :-)

there is a later model "Tensioned" type, which consists of a double shouldered cam gear with 2x rubber rings (one each side) on which the chain runs

alternatively you can opt for the leter A= type tensioned assy, which would necessitate the entire removal of "all" what you have there & total replacement -change-over to the A+ assy,,, front engine plate, tensioner assy, cover etc included

If you want to swap to double row then it`s easy,,, buy the gears & chain & fit them on, Making sure the gears are aligned with eachother, make sure you have the right oil thrower & fitted the right way round ,,,,, & there`s nothing to modify on that particular cover if you choose this option,,, i believe you may be thinking about the mods to a late A+ type single row cover that needs a "dent" put in it,,, your cover needs no dent, it will fit without mods
Author:  drmini in aust [ Sun Mar 21, 2010 9:00 pm ]
Post subject: 
Yeah I would fit a duplex chain and sprockets.
You need to countersink the 2 bottom holes in the engine plate and use csk screws.
If you have a reground cam, I would time it in properly the the supplier's specs. You can do this with offset cam keys (std sprockets) or a vernier sprocket set. I like the former method (just as good, but cheaper). :wink:

[edit] the sprocket with the rubber rings is the early type, not later. The rubbers go hard eventually and don't work anyway. :lol:
Author:  jester99 [ Sun Mar 21, 2010 9:01 pm ]
Post subject: 
ok thanks for the input matt. cheers
Author:  jester99 [ Sun Mar 21, 2010 9:02 pm ]
Post subject: 
ok thanks drmini. cheers
Author:  blue_deluxe [ Sun Mar 21, 2010 9:03 pm ]
Post subject: 
All i had to do when i fitted a duples timing chain on my 998 was countersink and put different bolts to attach the plate to the block, but you can see which ones when you get it and trial fit it.
Author:  TheMiniMan [ Sun Mar 21, 2010 9:16 pm ]
Post subject: 
hee hee,,, oh yeah i forgot to say the 2 bolt holes need countersinking :-( I really am loosing it :-)

& Doc,,, Just for the sake of argument,,, the std single row (Non-tensioned) was produced first,,, then they made the rubber ring type to help stop the clatter,,, but they didn`t make enough of them & actually ran out of stock of those ,,, yet they had sooooo many sets of non-tensioned ones & didn`t care to much to fund a re-make of the tensioned type that they just fitted the non-tensioned type into all the later small bores ... they only made small runs/batches of the tensioned type gear for replacement parts

true story
Author:  blue_deluxe [ Sun Mar 21, 2010 9:17 pm ]
Post subject: 
TheMiniMan wrote:
hee hee,,, oh yeah i forgot to say the 2 bolt holes need countersinking :-( I really am loosing it :-)


I had to read your post a few times to make sure i wasnt repeating you. I didnt believe it. lol
Author:  jester99 [ Sun Mar 21, 2010 9:17 pm ]
Post subject: 
i noticed with this much play in the timing chain i could turn the crank one whole tooth to the cam gear before the slack would take up.

is that considered normal? how tight should the new one be? is there any particular need for a chain tensioner or is it fine like this but upgraded to a double row version?
Author:  TheMiniMan [ Sun Mar 21, 2010 9:20 pm ]
Post subject: 
sorry to say "it`s normal",,, it`s noraml wear & slack for an old "non-tensioned" wornout old single row gear & chain assy yes,,,, it`s not concidered "Normal-workshop-practise" to have this amount of play tho

i`d have it sorted with a double row or at least a tensioned type gear assy & make sure you dial the cam in correctly when you do the job

like the good Doc said,,, do it once, do it right & it will go harder, smoother, & quieter
Author:  drmini in aust [ Sun Mar 21, 2010 9:22 pm ]
Post subject: 
No tensioner needed really with a duplex chain. The best one is an Iwis, made in Germany. More expensive, but worth it. These have virtually NO slack when assembled.
The UK ones on the other hand.... :roll:

Matt, my 1961 850 had the rubber tensioned sprocket from new. I've only seen the flat ones from mid 70s on. Cheapskate sprockets.... :lol:
Author:  jester99 [ Sun Mar 21, 2010 9:25 pm ]
Post subject: 
is there any need to get a vernier or high quality version double timing kit or can i just buy one of these?

http://www.minisport.com.au/prod374.htm

and just double checking if i fit a double row setup i will need to dial it in? or do i just buy a bolt on one like above?
Author:  drmini in aust [ Sun Mar 21, 2010 9:27 pm ]
Post subject: 
That will do fine on a road car. :wink:
You should fit it using the stock key, check the timing, and fit an offset key if needed.
My belt drive setup is waiting for the Boeing to land with a 5° key... :wink:
Author:  jester99 [ Sun Mar 21, 2010 9:27 pm ]
Post subject: 
i dont know what brand or type or size the cam is so i wouldnt be able to time it anyway would i?

will i need to remove the cam to get the brand and type? will it even be on the cam?
Author:  jester99 [ Sun Mar 21, 2010 9:29 pm ]
Post subject: 
ok cool, yeh thats seems a good option in my mind, its a bolt on job and will be fine on a road car engine. i dont plan on getting every available horesepower out of it so that should work fine.

thanks for your input guys. greatly appreciated.
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