Timing Chain, is it time?

[LoneWolf]

Well My 318is has about 105,000 miles on it now and I am thinking it may be a good idea to do some preventative maintenance.

The thermostat has just recently went out and needs replaced. I also have an oil leak to track down. I want to take care of the mess under the intake and replace any crack lines. Check out the oil pan bolts and loctite them. Annnnd I want to delete the clutch fan set up for an electric one. I am thinking that it would be best to do all of these things while under the hood at the same time.


I have been looking over brendan's write up here: http://www.esatclear.ie/~bpurcell/318istimingchain.html

Seems pretty straight forward with a few special tools/techniques.  

I was just taking the part numbers he lists, copy and pasting into pelican. BUT I realized that some are listed as m42 from 92-93???

Will this parts list not work for my 91? Are the gaskets and such different?

Any input or suggestions for my undertaking would be appreciated.

Edit: And I forgot to ask, If I pull the timing cover and my guides aren't showing wear and neither are my gears, do they have to be replaced? Or will a new chain and tensioner suffice?

I guess I am just a little confused after also looking at Sheepdog's write up. He replaced more I believe because of a cracked timing case??

Thanks

[LoneWolf]

Bump

Any input on compatability of the different part numbers??

Ordering tonight.

Thanks

[d.hitchcock]

If you pull the front of the engine, I'd be tempted to go ahead and replace all sprockets, the chain, tensioner, and all guides, as well as the thermostat, water pump, etc.

Stopgap would be replace the tensioner and its accompanying guide, the other side guide and the lower and upper guides.

[DesktopDave]

There were a lot of parts updated as the M42 went through production.  The 92-3 motor likely has the updated tensioner and guides went to plastic from metal/vinyl.  The later motor also eliminated the chain idler gear (has a deflector rail instead and the lower inner timing case was modified) and went to a serpentine belt setup.  There was an oil check valve update as well.

Even the much later >96 M44 has a lot of similar parts that can swap over.

I'd inspect & replace only as necessary.  Doing the whole deal can get expensive.  Given, it's a lot of work to R&R that case, so I'd err on the side of replacing rather than reusing...

[LoneWolf]

Thanks for the input.

I went ahead and ordered the parts I needed to take care of my oil pan and thermostat.

I am holding off on the timing chain and electric fan until I do some more research and feel comfortable doing them.

The electric fan seems pretty straight forward, I plan on using the later m42 electric fan set up that bolts right in from pelican.

The timing chain is the only thing I am leery about, considering a couple of the threads I have seen about it.

[Gabs]

Cant stress enough the Importance of finding Top Dead center and locking the cams or marking the cams. Made the mistake while attempting my first timing rebuild. Cant quite remember where I went wrong now, had the cams locked but I think my makeshift cam clock failed me. Had to go back and open everything back up, adjust the intake cam, now everything is lined up. Though I believe I have a bent valve from my first attempt, The M42 runs but its making a racket and running oddly.

**Just recalled what happened, after putting new cam gears on, I believe when tightening the gears, my makeshift holder allowed the intake cam to move ever so slightly. So word to the wise, Invest in or borrow a cam locker.

Aside from that, I didn't find it to be a difficult task, Time consuming but not extremely difficult. It depends on your mechanical inclination I suppose.