Timing gears

[Burdekin]

Originally Posted by sleek lemur

So is that steel or Alloy, Burdekin?

From their website, I haven't actually taken out of the packet yet and is what Ben recommended so just went for that.

[Burdekin]

Originally Posted by sleek lemur

Hi all,

Surprisingly, I couldn't find any conversations on this subject in forum history. My B18A rebuild will be fairly standard, but with K cam and 9.5:1 CR. What timing gears are recommended? Alloy would be tougher than fibre and cheaper than steel, so that's what I'm minded to use.

Unless anyone knows better.....

I am doing a light upgrade to my B20A, bought and recommeded from Ben at Tinus Tuning in the Netherlands: https://www.tinustuning.nl/1-onderde...kkenassen.html still not cheap and wanting more acceleration rather than chasing max HP. He also didn't recommend increasing the CR apart from the thinner head gasket, not sure what that will take it too.

[sleek lemur]

Many thanks, Burdekin. Alloy it is.

[142 Guy]

The alloy / steel gear set linked by Burdekin looks just like the Cloyes timing gear set (I expect that there is not a lot of competition in the limited market for B18/B20 timing gears). Available from Rock Auto for the equivalent of about 75 pounds sterling or 83 Euro before shipping and duties.

https://www.rockauto.com/en/catalog/...iming+set,5756

Note that if you are pricing them out, some vendors (CVI and others) include the ancillary bits to facilitate replacement of the timing gear set. I believe the Rock Auto Cloyes set is just the gears. Factor that into your price assessment.

I still have the 180,000 km + fiber set in my B20E. When I did my engine rebuild, I don't recall reassembly of the timing gears being a particular challenge or requiring special tools. However, if you do an internet search you can find cases where the installation has been botched, sometimes spectacularly. You may want to give some consideration as to whether you want to purchase the purpose built installation tools for the gears (I didn't).

As a final note. There is a removeable hub on the crankshaft where the crankshaft pokes through the front timing cover. With the original felt timing cover seal this hub may (likely will) develop a groove where it contacts the felt seal. If the hub has a groove a new seal will never seal. Check your hub for wear and if there is a contact groove replace it. With a little machine work you can upgrade the timing cover to a modern lip seal. However, unless you can do the machining yourself it is probably cheaper just to purchase a complete new cover already fitted with a lip seal

[sleek lemur]

Gosh, thanks for such a thoughtful reply, 142.

I will go with the alloy and you are correct, Brookhouse over here in blighty do a remodelled timing cover with a more modern seal.

I actually dreamt my engine was back from the machine shop last night. I've got it bad!

[Burdekin]

Originally Posted by sleek lemur

Gosh, thanks for such a thoughtful reply, 142.

I will go with the alloy and you are correct, Brookhouse over here in blighty do a remodelled timing cover with a more modern seal.

I actually dreamt my engine was back from the machine shop last night. I've got it bad!

Be careful with the neoprene seal swap, the seal in some now are thin and not much chop and leak worse than the felt.

[sleek lemur]

Why oh why does there always have to be a "but"?

I had heard of poor sealing with the rear crank seal, but not the front. I will interrogate Brookhouse prior to purchase.

[Burdekin]

Yeah talk to Simon, he'll steer you right.

[Derek UK]

The crankshaft nose sleeve can be reversed to hopefully give a smooth unworn surface. I don't think the seal runs dead in the middle. They are available new but they are about £70(?). With a clean surface to run on there is nothing wrong with a felt seal. Soak with oil before fitting and you will get at least 50k miles out of them before they start to go hard. A cheap and easy change once you get the pulley and sleeve off.

[Laird Scooby]

Originally Posted by Derek UK

The crankshaft nose sleeve can be reversed to hopefully give a smooth unworn surface. I don't think the seal runs dead in the middle. They are available new but they are about £70(?). With a clean surface to run on there is nothing wrong with a felt seal. Soak with oil before fitting and you will get at least 50k miles out of them before they start to go hard. A cheap and easy change once you get the pulley and sleeve off.

Another option would be a shaft repair sleeve or alternatively, one of these two methods :

1. Remove the crank nose sleeve, take it to an engineering workshop, run a bead of weld round the worn part then turn and polish it in a lathe to the correct diameter and smoothness.

2. Remove the crank nose sleeve, clean it and then copper plate it. Heat with a blowtorch and fill the wear groove with solder. Smooth off in a lathe (or drill if you can clamp it) and polish with Emery cloth. Degrease and then copper plate again and finally nickel plate and polish that to a high shine.

I'd suggest using a rubber shaft seal (i've seen something above that indicates these are available) if using the last method but all should work to repair the crank sleeve.