Classic cars forum & vehicle restoration.

Kelsham · Posted: Thu Aug 02, 2012 1:32 pm Post subject:

Jim, don't let one rude person put you off trying to help by offering advice.

I personally will not be replying to any of his posts unless he offers an apology to you.

Regards Kels.

Bitumen Boy · Posted: Sun Aug 05, 2012 12:07 am Post subject:

Kelsham · Posted: Sun Aug 05, 2012 9:30 am Post subject:

Good, spat over and all friends again.

I had a somewhat similiar problem when I had the unleaded conversion done to my Morris 1800.
As I removed the cylinder head I noticed the temperature sender was very vulnerable.

So I decided to remove it whilst the machining was being carried out.

When the head was put on I refitted the sensor and installed a new thermostat.

The car never seemed to run correctly afterwards. I had also fitted high compression pistons and changed to a suitable distributor. It would ocasionally cough when running at speed and spit back.

The sender had resented being disturbed and stopped sending messages to the gauge.

I ordered a new one and when fitted it read low. It was a different pattern to the one it replaced.

I contacted the supplier and he admitted that one or two others had experienced similiar problems and had complained. Most were satisfied.
I accepted the explanation. My car is an early model and probably needed an odd ball sender.

Kept investigating the poor running, eventually found that the new thermostat was stuck open. I replaced it and the problem was over.

Does your car recover when you pull the choke out? This was the clue that led me to the explanation. Gauge now reads correctly?

The other point is the replacement head. Are you sure it is identical to the one removed?

Kels.

Bitumen Boy · Posted: Fri Aug 17, 2012 7:45 pm Post subject:

At last, something to report on this one, having had some time to work on it!

Kelsham, whatever the problem turns out to be, it is at least warming up properly - registering on the gauge as normal and confirmed by the underbonnet temperatures while leaning over the engine scratching my head... As to the head, no, it's not exactly the same as the old one, though the difference by eye seems limited to having two core plugs in the rear end of the head instead of one larger one. Combustion chambers and valves look the same, though if I end up having it off again I will measure up and check. I did order the recon head according to the engine number on the block, so it should now be the right one for the engine - though whether the old one was right is anyone's guess, you know how things get swapped around on old cars. It isn't the original engine for my car, that was still just capable of moving under its own steam when it started knocking, and given the location of our garage, I wanted to keep it that way as long as possible, so I sourced another unit to rebuild - an 1147 from a mk1 Spitfire (by the engine no.) in a crumbling Herald that wore a 13/60 front end, though heaven knows what it started out as! I've tried giving it a bit of choke, it seems to help initially but not for long, if that makes sense.

Anyhoo, this week I finally got round to checking the timing. Not sure now whether it was out, as in attempting to check it for sure (by feel) I lost the previous setting Embarassed

but found that the chain tensioner was completely knackered - after only around 5k miles, so I'm pretty narked about that - but it's easy enough to re-time from scratch, and at least it's not been a waste of time whatever the eventual outcome. I was initially worried in case the tensioner had failed due to lack of lubrication, but spinning the engine on the starter with the timing cover off resulted in a small oil slick on the garage floor, so it looks like it was just the usual lousy quality of remanufactured parts, it had the spring but not the hardness!

Currently waiting on parts, and not going to get anything much done again anyway with work so that's it for now. Hopefully an end is in sight, but if not the head will have to come off again Rolling Eyes

Bitumen Boy · Posted: Fri Aug 17, 2012 8:00 pm Post subject:

Just realised I forgot to mention the results of the paraffin test on the inlet manifold. I left the paraffin in for 4 days, during which time it lost maybe a little more than a tablespoonful. It hadn't leaked out around the manifold to head joint, nor had it got into the exhaust - I ran it to ground in the cylinders, about an equal amount in each. I'm inclined to think that small leakage of paraffin, past four inlet valves in four days, isn't terribly significant, though it beats me why it didn't leak the other way when I tested the valves prior to fitting the head Confused

Bitumen Boy · Posted: Sat Sep 01, 2012 9:13 pm Post subject:

Finally got the timing reset with new chain and tensioner and have been on a couple of local test runs. It feels better, but not there yet - which is pretty much what I expected. While trying to set the timing I found I couldn't really turn the camshaft by hand, and to set it on #1 cylinder I had to remove pushrods 3-8, and I don't remember having trouble with this before. With the pushrods removed, the cam turns by hand no problem so it's either over-firm valve springs, one or more sticky valves or possibly a bit of both, so next time I can work on it it looks like the head is coming off again for further investigation and - hopefully - rectification. What fun Rolling Eyes

47Jag · Posted: Sun Sep 02, 2012 12:20 am Post subject:

Are these the pushrods that were popping out in July?

Art

Bitumen Boy · Posted: Sun Sep 02, 2012 2:19 pm Post subject:

It was only #1 pushrod that jumped out. It did it twice in quick succession, then nothing - yet... Know it's been a long time on the calendar, but actual garage time has been very limited Sad

Bitumen Boy · Posted: Mon Sep 10, 2012 4:28 pm Post subject:

Finally some progress to report on this. Had the head off again, and stripped it down. The springs are definitely firmer than original but there's also an obvious fault found - #1 valve is sticking. Not rock solid, doesn't take a hammer to move it, but definitely not right and it obviously isn't going to resolve itself. Question is what should I do now? The simple and obvious thing is to away back to the guys who supplied it, and let them sort it - and talk to trading standards if they don't play ball. But even if they are perfectly good about it that still means lots more time and hassle, and so if anyone has any clever ideas for freeing off one sticky valve I'm very interested to hear them!

I'm kicking myself now for not stripping and inspecting it before fitting, but I was pushed for time and thought "reputable supplier, won't be any trouble..." Evil or Very Mad

RUSTON · Joined: 07 Mar 2011 Posts: 144 Location: Matlock.

Is it the valve that is at fault or the guide? Try another valve in the guide, if that is free then it is the guide itself, then contact the supplier and give them some stick!

Pete.
_________________
Measure twice...cut once!

Bitumen Boy · Posted: Mon Sep 10, 2012 5:52 pm Post subject:

Good thought - will have a look later Smile

Bitumen Boy · Posted: Tue Sep 11, 2012 1:04 pm Post subject:

Had a play and it would seem that the valve itself is at fault. I've tried #1 valve in the other 3 exhaust valve guides, and it binds to some degree in all of them. When I try the other 3 exhaust valves in #1 guide, however, they all run freely. I will be getting on to the suppliers as soon as I can find the invoice - know I put it away safely, just not 100% sure where... Rolling Eyes

Bitumen Boy · Posted: Wed Sep 12, 2012 1:46 pm Post subject:

Hi guys,

I phoned the suppliers yesterday and this morning a new valve and headgasket set arrived in the post, gratis - not that they would have gotten any more cash out of me for them! New valve is fine in the guide and now lapped in, but having to do the rest means my original aim of having it sorted for the weekend looks unlikely Sad

I'm not at all impressed with the standard of workmanship on this head, OK the valves didn't leak when I tested them with paraffin prior to the first fitting, but the exhaust valves and seats look very much as if they've been machine cut and not lapped with grinding paste at all, indeed if they had been lapped whoever was doing it would have noticed that sticky valve. The inlets are a bit better, but I still wouldn't be happy about refitting the head without doing some further work on them. If ever I did another unleaded conversion and went any distance for an exchange head I reckon I'd take my valve spring compressor and check it over in the car park before leaving... Twisted Evil