OHV Camshafts

[Spunkymonkey]

Ok, so having checked Sheila's valve lift it seems I really should be replacing her camshaft right about yesterday. So what's likely to fit?

The block is an early (earlier than the car) 1300FWD one, so I'm assuming she doesn't have cam bearings fitted and will have the 1.965 inch journal size of the 1300 SC. Is that the same as the Spitty Mk IIIs that people seem to recommend, or do they use the smaller 1.840 inch journals and bearings like the 1300 TC?

I'd rather have something that's a straight drop-in cos pulling the engine to change it isn't practical around here. Any advice gratefully received here cos I really want to make her again ready for summer!

[1300dolly]

camshaft part number is 212359 also used on heralds, its only the TC camshaft, 212164 that was fitted to the spitfire 4.

[Spunkymonkey]

Cheers, Justyn. So where Rimmers and Paddocks list the 212164 for Heralds and Spittys I - III that only applies if they've had the bearings retro-fitted, and the RKC3305 that they list is an alternative to the original. Is that about right?

[1300dolly]

Not to sure to be honest, as for the RKC number that will probably be a later one, likely dolly 1300. Jod may be the man to ask about cams.

I will dig out all the cams i have later this week.

[Spunkymonkey]

Paddocks are listing the RKC 3305 one for Heralds and Mk IV Spits. For Heralds they list it as "big journal" and the 212164 (which Rimmers give for spitty late Mk II, Mk III and early Mk IV) as "small journal". They list the 212164 for all Mk I to III Spits.

Rimmers, on the other hand, on their Spit pages, say:

Original Block Specification Mk1 camshafts ran directly in the cylinder block, as did early Mk2’s up to engine number FC61022.

Cylinder blocks for Mk2’s (from FC61023), all Mk3’s and early MkIV’s (to FH25000E), had enlarged drillings in the cylinder block to accept replaceable camshaft bearings (part No RL1495), though the camshaft journals remained the same diameter.

Late MkIV (from FH25001E) and all 1500’s had revised cylinder blocks allowing the camshaft to run directly in the block without the use of bearings.

And they list a 211433 for 1200 and 1250 Heralds and Mk I / early Mk II Spits, then the 212164 for late Mk II, Mk III and early Mk IV Spits, and RCK3305 for "all other models" of Herald, later Mk IV Spits and all 1300 and 1500 Dollys.

You see why I'm getting confused here?

If any of yours have 1.965 inch journals and 8 whole lumps instead of the seven-and-a-pimple that Sheila's seems to have then it'd probably be an improvement

[2F45T4U]

I'll find out what I've got

[Spunkymonkey]

Cheers, Adam. Justyn is looking as well but if there's no luck then I guess I'm going to have to bite the bullet and buy a new one next month before the new followers get wrecked as well Of course, then I won't be able to afford any petrol for her but at least she'll be able to sit still without tapping

[Spunkymonkey]

Ok, quick question on this for those with lots of OHV experience. When a replacement shaft arrives (hopefully in the next week or so) I'd rather not remove the head again to fit it - cos I don't really want to order another head gasket and anyway I'm lazy.

But the valve lifters need to be out of the way to remove the camshaft. So, can anyone think of a good reason for not getting a pack of magnets and gluing them onto dowel to make magnet-lifty-rods to lift them out of the way while the shaft is slid out / in?

The only potential "oops" I can see is, if I drop one with the camshaft out, how far would it drop? The idea of having to pull the engine cos I was trying to save time - that don't impress me much

[JPB]

I've not tried that trick on Triumph OHV motors, but on the Reliant 750 & 850 (in blocks that had been machined to accept A-series tappets, meaning that the lifters were then too big to come out through the pushrod holes which I'm assuming isn't an option with the Triumph motor), the done thing was to use slim Rawlbolts.
Put the expanding ends of the Rawlbolts in the lifters, cut threads in a piece of steel larger than the pushrod hole to act as a means of winding the claws up, screw down on the centre of the Rawlbolts to spread their claws, then turn the bolt head which will, in conjunction with the threads that you'd cut in the steel plates, pull the lifters up out of the way and hold them there. Nice & gently does it when you pull the lifters up, those claws could still relax their hold inside them, but a darned sight more secure than magnets and bits of timber, IMHO.....


However.....

Would it not be wise to use fresh tappets with your new camshaft, in which case the head would have to come off?

[Spunkymonkey]

Good idea with the rawlbolts - I was trying to think of expandy things to use but they didn't occur to me

As for the lifters, I replaced them while I had the head off in a "hope the camshaft's alright" moment so they've done all of 225 miles. Given that the camshaft must be well through its case hardening by now, I figure it's worth a small gamble that new, hard, lifter faces won't have suffered too much against soft cam lobes in that sort of mileage.

[JPB]

Yeah, you should get away with the lifters then. Happy spannering!