Lotus Elan

Cams and timing query..

PostPost by: avro » Wed Jul 31, 2019 7:53 am

Mel

My first thoughts when l looked at the picture was that someone had modified one of the wider bearings in the bearing pack to fit into the rear housing. Perhaps they had lost one of the four narrow bearings and had modified a wider bearing to fit. ( l’ve seen this done before ). As the position of the bearing tang differs on the sixteen wide bearings to those of the four narrow bearings in the pack this overhang into the cam follower bore would have been the result.
However the narrow bearings designed to fit into the the rear housings don’t have oil feed holes, so this is the correct bearing . Your picture doesn’t quite show the position of the bearing tang retaining groove that is machined into the head so l can’t see if it’s been machined slightly out of position . This could be the likely explanation and hence the need for a spot of grinding.

Nick.
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PostPost by: 512BB » Wed Jul 31, 2019 9:12 am

I wish you would get on with my heads Nick instead of posting on here :lol: Whats that...........you are having your breakfast. Oh, okay then, I will let you off. I would think that your hankerchief needed wringing out a few times, by the time you got home last Thursday. Keep well.

Mel wrote 'next find was a considerable amount of very old and smelly oil in each head bolt hole
Bolt threads came out really covered in it and really carbonned up.
It absolutely stinks & has me a little concerned as the previously drained oil other than having a slight whiff of fuel (hardly surprising given the above) seemed quite clean'

In my experience, the bolt holes always smell like that, no matter how often the oil has been changed. I rebuilt an engine from one of my cars last year and the oil in the bolt holes smelt pretty foul, even though I had changed the oil every 3k miles since its last rebuild. I put it down to the oil in the holes just staying there once it has filled the hole, and not getting flushed out with an oil change. Thats the only explanation I can come up with. I only use mineral oil, synthetic may be different.

Re your scored bearings, you are correct. You would expect to see some wear marks on all bearing surfaces after thousands of miles, but you should not see grooves cut into the bearing surfaces. That, as you say, has been caused by dirt / swarf, whatever, due to poor cleaniing out of the internals when last rebuilt. You cannot clean an engine enough when rebuilding, preferably by hot tank or ultrasonic cleaning, after EVERY bung has been removed. And then observing scrupulous workshop cleanliness when building up. I would think that many of your other shells will look the same.

Good luck with it.

Leslie
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PostPost by: 512BB » Wed Jul 31, 2019 9:13 am

Duplicate post, deleted.
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PostPost by: rgh0 » Wed Jul 31, 2019 9:37 am

Hard to tell from the photo but maybe a full width shell has been cut down for use in the half width shell positions at the rear of the head

cheers
Rohan
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PostPost by: Sploder90 » Wed Jul 31, 2019 6:39 pm

Will see if I have a clearer picture on the phone but the offending article is now out (& sitting in a Ziploc bag)

Big ends and mains look ok but these are also part of a general refresh programme.

Not got the valves out yet so let's see what else there is to find.

Looking forward to the part where the only difficult bit left is finding a paint code for the engine grey :D

Anyway if I couldn't take a joke I should never have joined the club...

All part of lifes rich pagent.... :lol:
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PostPost by: Sploder90 » Fri Aug 02, 2019 11:30 pm

Well the head is going away for some work next week.
next thing on the list is the bottom end refresh & then refit the water pump.
& a tidy up of the engine bay while the block is out. (& new loom looking advisable..)

Hopefully no more surprises in store...

Anyone heading to Croft retro over the weekend?
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