Hey,

Lately I've noticed that at lower revs, esp during idle, the engine on the radiator side rattles abit. I thought it could actually be the radiator fan itself knocking against a dent in the radiator cowl, or the fan pullets were playing up.

When Dr Mini pulled my alternator out it seems that the fan belt is in ok condition.

I read yesterday in my performance book that the timing belt on stock 1100's can wear their tensioning bushes and start knocking at 100,000kms

1) Is it an engine out job to replace the timing chain?
2) is it worth changing it to double row timing chain?
3) What's the worste case scenario if I don't do anything about it?
4) What else could it be?

Cheers boys!

_________________
Lillee - 1969 Morris Mini K

1)can be done in car
2)yes it is worth changing over
3)cam and dizzy timing gets out,chain could snap and put a valve ( or valves) through a piston , very unilikely tho .
4)radiator could be loose in the shroud

_________________
lookin for another clubby

Howdy,

Sounds like timing chain, I replaced mine without removing the engine, just have to remove radiator to get at it. Twin row chain will last a LOT longer than single, but have to counter sink the backing plate and use allen headed bolts to clear the chain. This is hard to do with the engine in place. Also, make sure the inside of the timing cover will ALSO clear the new setup. I had a little prob with that !

Anyway, worst case is more a lack of performance as the timing wanders about, unless this becomes too bad you could leave it for a little while. Someone please correct me if I'm wrong on this one!!

Cheers,

Matt

Thanks guys, is it easy to check how worn the timing chain is? or is this a radiator out job at the minimum?

_________________
Lillee - 1969 Morris Mini K

Rad out job. Hardly worth checking it unless you are gonna change it.

If you put a new single row chain on it, that will shut it up for a while. All it will cost is the chain, a seal and timing cover gasket. Around $20-30 if U do it.

Just make sure you line up the timing marks properly....

Converting to duplex setup is easiest with motor out, as stated above.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I took it for a spin last night and the "clicking" and rattling is very noticeable now at idle. It is definately coming from somewhere low on the radiator side of the engine. The fan/alternator belt looks well aligned and spinning freely so I doubt that it's the problem...

Hrmm might have to do some surgery eh?

While I was poking around down there yesterday I also noticed that the radiator bottom hose has seen better days... might also be worth replacement since it's a radiator out job.

I'll bring her over to show you later on Doc, so you can give me a diagnosis

_________________
Lillee - 1969 Morris Mini K

how much slack should there be in a timing chain when poking the back side of it? (i have the timing cover off)

Not much...
If you've got the cover off, fit a new chain, they are cheap.
But make sure the sprockets are not worn.

If you are going to modify the motor much, I'd fit a duplex chain & sprockets. They last a lot longer.

BTW, some chains are better made than others. The best I've seen lately are the German made `endless' ones, but they cost more.

<edit> As the chain wears, the valve timing gets retarded and you get more `spark scatter' ie, the ign timing varies about as it's revved.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I think I recall somebody mentioning that going to a rubber belt is also an option? Do they last longer and/or are less susceptable to slackening off?

dewey

_________________
dwightgunning.com

Dewey,

I run a timing belt kit in my 1310 instead, & I change the belt every 40,000 miles. They don't stretch like chains do. You just need to change them regularly, before they break!
Kit is bloody expensive now, though.

<edit> there is no tension adjustment. belt is a tight fit when slid onto `gears'.
After 40,000 miles, it is still the same tension and looks new, but I won't trust them any further- they are a very short belt (52T) so go round lots more times in 40,000 miles than yer average Jap engine one does.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

well i can push the chain in about half an inch at the back (front is tight)
so i will change it

does the timing belt kit have a different front covver to carry oil seals

cause i dont presume you can run a wet rubber belt setup

It uses a different setup.
See
http://www.minimania.com/web/SUBTYPE/Se ... entory.cfm

it's 1/2way down page. Seals are different too.
Replacement belts over here are $60 approx.


<edit> the US$269 one is what I have. Once you time the cam in properly with the right offset key, you won't ever alter it anyway.

Probably cheaper to buy from MiniSpares UK....

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

While you are at it, take a look at the rocker gear as this is also a source of rattles and shakes(worn rocker shafts...). It is a pain in the butt but well worth it.

When doing the timing chain also remember that the backing plate has to be countersunk(as previously mentioned...)but it is easier and more accurate if you remove the plate from the car as if it is in the car the bit may grab and rip up the hole pretty badly(trust me on this...lol) amd better still use a pedestal drill for the job. Also check the timing chain cover as well as if you had an earlier model mini, these covers had a half hemisphere shroud on the inside on the crank hole - this will have to be ground off so as not to foul the new duplex chain.

Definitely go the duplex as well as it is stronger(I believe there is a triple now!!!??)and will definitely have you on your way.

Hooroo for now

Skins

_________________
Rob Forsyth
Miniot!!

Rob, the `triple' is not really a triplex chain, it's a Morse so-called `silent chain'.

Nothing real new about it- WW2 Jeeps had it..

I agree a Duplex is the way to go. Watch how loose the new chain is though- British made chain ain't what it used to be..

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Thanks mate - saw one in one of those pommy mags - looked pretty flash. Going out to finally put the 1.5:1 "S" rocker assembly on the clubby - Wife is going to love me for that...lol

Skins

_________________
Rob Forsyth
Miniot!!