Rattle

[RDfella]

Greybeard - the modern motor car. Aaaarrrrgh. Nowadays it's not mechanical issues that cause breakdowns, but electronic ones - which can be a nightmare to fix. Ask any Rangerover driver. As for the modern bus system - merely a glorified spur system.

[Greybeard]

Ok, today I actually made a start on investigating the noisy engine in my Plunger A10. As the engine is only noisy when hot I was fearing that I may not find anything when I stripped it. I took the head and barrel off. Both exhaust valve faces are pale but the primary side one is very white. I think this is because I've been running with tight tappets, (to overcome engine rattle) and the exhaust valves have got too hot. When I took the cylinder barrel off I found this:

The camshaft doesn't look too bad but I guess I'm going to have to strip the whole lump to measure it.

During my recent work, I found the brand new cam followers that I'd bought from one of our normal suppliers had been chewed up. The suppliers said I must have been responsible for the damage. I was all set to argue about this but then I found that I'd put the sump mesh in turned 90° so the pickup was against the mesh. I have to admit that oil shortage probably caused those followers to wear. I bought a set of SRM followers and of course fitted the sump filter correctly.

Now, this! Might this damage be due to the previous oil flow shortage?

Can I have your comments please.

[duTch]

 umm- yuck.... .....How's the camshaft? Was that one valve tighter than the rest?

[Greybeard]

 umm- yuck.... .....How's the camshaft? Was that one valve tighter than the rest?

DuTch, why are you awake?

I've added some more information to that post. I have not taken the valves out of the head.

The tappet that corresponds to that follower needed frequent readjustment so I suspected something was wearing.

[Greybeard]

This picture is from my last strip. These are the non SRM followers

[berger]

i have not been to the pub, Greybeard you could try a file across the untouched part of the follower and see if it digs in or skids off , it could be a butter part seeing as the others seem ok

[JulianS]

Poor case hardening most likely. Poor lubrication would have shown up on the others. The cam trough being copiously fed with oil from the feed side of the pump and supplemented by oil draining down from the rockers. Seen badly worn followers before but that is the worst.

[berger]

greybeard the cam trough gets most of its oil when the prv releases and shoves oil to the tiny hole for the timing gears and shoots it up a drilling to the trough. and looking at the others the trough hasn't been starved, a camshaft pic would be nice, ime thinking a shite follower

[Greybeard]

i have not been to the pub, Greybeard you could try a file across the untouched part of the follower and see if it digs in or skids off , it could be a butter part seeing as the others seem ok

To paraphrase the M&S advert: These are not just cam followers; these are SRM cam followers! I'll check them though.

[duTch]

 

...DuTch, why are you awake?...

 Sorry mum- my eyes fell open n'n'n I'm waiting for the punkins to grow, n'n'n had to check the stars are still there, n'n'n had to warm the Teve to watch the Moto's go 'round in circles, n'n'n it'snot even midnight yet.....n 

[Greybeard]

Pics of the camshaft and one of the exhaust valves

[RichardL]

I was expecting to see a cam in worse condition. Regarding measuring, rather than starting with complete disassembly, I think you could lay a reference across the top of the crankcase and measure down using a caliper. Should give accuracy within a few thousandths.

Richard

[RichardL]

Oh yes, very sorry to see this. I know you were very much looking forward to the DGR, but moreover, to just enjoying your bike and not just fixing it.

Richard L.

[berger]

did you try the file? camshaft looks ok so  i'm going for rouge follower

[RichardL]

I think you need to send the photos to Gary Hearl at SRM and give him a call tomorrow. I'm pretty sure no one has seen or done more A10 rebuilds than SRM. I'm sure they will have an opinion and they need to see this.

Richard L.