V8 camshaft retaining plate?

Question

I've just got a new camshaft for the 3.9i I'm rebuilding for the 110. It's one with the step machined into the end by the timing gears to allow it to work with the retaining plate fitted to the later engines. I know the interim engines (gear driven oil pump and dizzy) had a full- circular retaining plate and then on the 4.0 and 4.6 LR moved to a semi-circular plate. Does anyone know if the critical dimensions are the same for both types of plate (i.e. will either work with my cam)? The semi-circular ones seem easy enough to get hold-off, the interim ones less so - in-fact I can't even find a part number for them.

I'm assuming it's a good idea to fit one - it's just a case of drilling and tapping a couple of holes in the block (avoiding oil ways) and I know the original method of location, relying on a taper on the cams reacting against the lifters, isn't considered a particularly great bit of engineering.

Cheers,

Andy.

GbH · Accepted Answer

Ask Badger, I'm sure he will know.

AndyC · Answer

Yes, hopefully he'll be along with his vast wisdom.

Digging a bit further, it looks like the thrust plates are different, with the 4.0/4.6 having a smaller diameter. As my cam was sold as for a 3.9, it looks like I'll need the larger, interim, thrust plate - anyone know its part number?

AC.

Badger · Answer

Yes, hopefully he'll be along with his vast wisdom.

Digging a bit further, it looks like the thrust plates are different, with the 4.0/4.6 having a smaller diameter. As my cam was sold as for a 3.9, it looks like I'll need the larger, interim, thrust plate - anyone know its part number?

The plates are indeed different and you need the right one. Sorry, I don't have the part number to hand, but be carefull when drilling the holes as they are offset slightly below the cam centreline to give clearance to the oil galleries. Badger.

Andrew Cleland · Answer

Thanks Badger. I'll keep digging for a part number and exercise care with my drill!Andrew.

Andrew Cleland · Answer

Just to follow-up on my own post, I think I have the correct part numbers now. If anyone else needs them, they are:

Thrust Plate, Camshaft. Interim, 3.9, - ERR5926

Thrust Plate, Camshaft. Late, 4.0/4.6 - ERR2609

AC.

Badger · Answer

Forgot to mention - be careful what thickness of bolt heads you use - you need clearance between the bolt head and cam sprocket, and the standard bolts are most likely a UNC thread. The thread, at a glance, looks like it's probably metric but every other thread in that block is UNC (regardless of bolt head size!) so be careful. Badger.

Andrew Cleland · Answer

Thanks Badger. The plate arrived today from Rimmers (pricey @ £11, but they're the only people who seem to sell it and it's a genuine part).

It looks like the holes are around M8, but I'll need to measure properly. There are no holes on the block yet, but assuming M8 is a good fit, then I have the necessary drills & taps, along with a box of nice M8 stainless button-head cap screws which should do nicely. I imagine Loctite is recommended.

AC.

Badger · Answer

5/16 UNC is very similar to M8, so you'll probably be ok with what you propose, and yes, loctite is your friend in this instance. You need a decent torque on them as well though, about 12 lbft from memory.....?Badger.

V8 camshaft retaining plate?

Join the Discussion

Didn't find your answer?