• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Head gasket

Share this page

I'll get the wet numbers tomorrow, the reason not done is that there was no oil around. I'll have it back in the morning when I plan to tune the SUs.
The BMC workshop manual I have, or any other manual for that matter, didn't offer a range, just a ratio and a pressure (120) and didn't offer a 'normal', 'OK', 'bad' or 'panic' set of numbers that my numbers fell into.
I've taken some comfort from Jeff's numbers though.
 
[ QUOTE ]
the reason not done is that there was no oil around.

[/ QUOTE ]
Barry, you could have wiped a pint from the bottom of the oil pan, fer cryin out loud!! It's a LBC!!!!!!!! /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif
 
If I wiped the oil away, it would rust in less than 30 seconds!! That stuff is the only thing holding the car together.

One good thing about the midget, it doesn't leak from the front, the rear axle drips a couple of drops a week, but the oil level and quality in the engine is remakably good, better than my Quest and the missus RAV4.
 
mehheh... mebbe you read the METRIC side of the guage?!? /ubbthreads/images/graemlins/wink.gif

...or the CC's are severely carboned.
 
[ QUOTE ]
...or the CC's are severely carboned.

[/ QUOTE ]

Interesting diagnosis Doctor; treatment, prognosis?

This car had not been driven over 45mph in 8 years (and only for about ten minutes), I took care of that in my first ten minutes of ownership, so I guess doing the 100m after 34 years of smoking.
I'm more and more tempted to do an engine rebuild this winter anyway, 'tis the only way to learn.
 
All those numbers are high but the same in all 4 cylinders - wet & dry - so your problem isn't valves or rings...time to go deeper.

Pull the oil pan with the engine in the car & rotate the engine & watch what happens in each cylinder hole...see if a rod is bent, loose or a piston is cracked or "slapping"...& you may find your problem in pieces in the oil pan!
 
That sounds really drastic....
I did tune the carbs today, a friend assisted and it turned out to be a hair rich, but not enough to be consistent with the symptoms.
Deeper it is.......
Thank you Tony, that pan isn't coming out until winter I think, classes have just started, no lift and a wife that is considering moving a bed into the garage..
 
The high numbers could be from the compression gauge being off. You could try another gauge or try the gauge on another engine. You can have excellent compression rings and have a damaged oil ring. Pat Goss gave me great advice when my sons Civic blew a head gasket. While I had the head off I wanted to check the rings as some fluid was in the cylinders. Was it antifreeze or oil? Pat suggested disabling the fuel pump and distributor and blocking off the oil passage to the head in the top of the block. Clean the cylinder walls and crank the engine for a total of a minute in several sessions letting the starter cool in between. If a significent amount of oil recoats the cylinder walls you have bad oil rings. I was in luck and didn't have to rebuild the bottom of the motor. If an oil ring catches on the cylinder when you insert the pistons it can be damaged enough to cause smoking on a brand new rebuild. Phil
 
If I'm looking for 'pieces or parts' in the pan, what kind of things am I looking for? I haven't changed the oil since I noticed this, is it something likely to come through the drain plug or bigger?
 
Before you get too far into it - follow your friend's advice & redo the carbs...they'll need it even if you decide to do the engine later.

When you drain the oil next time, look for metal particles in it...then take one of those little magnets on a stick (the type that swivels...stick it up in the oil pan drain hole & swivel it around to see if it picks up anything....if the oil's clean & you've got good numbers & no knocking or anything - he may be right about the carbs.
 
If I have this correct the only symptom you have is puffs of black smoke and there are no noises from the engine. If this is so there is no need to open the engine. You will need to adjust the carbs. Make sure the float level is correct. If it is too high you will be able to set the idle mixture correctly, but the other ranges can be too rich. With two carbs. you can have one set rich and the other set too lean. The engine will still run, but two cylinders will be rich. Make sure the choke linkage is free and both jets return to the non-choke position when you press the knob back in. The shoulder on the needles needs to be flush with the bottom of the air valve. The air valves must move freely in the air chambers with the dampers removed. The jet in the carb. body must be centered around the needle. The dampers must have resistance for the last 1/4" when inserted into the air chambers, or you need to add more oil. If you have all these things adjusted correctly the black smoke should be gone.

I would suggest you find an old lawn mower to rebuild first as practice, if you are not sucessful just throw it away and try again. It is harder to disassemble and reassemble a single cylinder motor with a rope starter and get it running than a multi-cylinder motor with an electric starter. Have fun. Phil
 
After four hours, I think I did the carbs OK, it sounds great, idle is about near perfect. I don't have an experienced ear to know for sure so someone will verify later. Rain is in the forecast so when that gone, I'll drive it 20-30 miles and see if those symptoms are gone or persist, try again....
I'm still looking for a used weber manifold, although this was a great learning experience, and kinda fun, it seems a little 'high maintenence' to continue, the technology behind SUs are good, but fragile. The next drive will tell.

I will be changing oils this week also, and will remain diligent to any stuff in the motor, I'll keep all options open, including the obvious....it's a 34 year old A-series.
 
Perfect!! /ubbthreads/images/graemlins/grin.gif
It growls nice, no puffs o'smoke, still used quite a bit of gas but I suppose that was right foot heavy, all in the name of research of course! /ubbthreads/images/graemlins/devilgrin.gif
Thank you all gentlemen, nice to get a result without:
a: Ripping the head of it...
b: $$$$
c: Doing (most of) it myself
d: Even the wife had a 'fly catching' grin

Again, my thanks. /ubbthreads/images/graemlins/cheers.gif
P.S. I think I'll keep those SU's around a little longer.

How much beer do I owe you all????
 
Once SU's are set up, they can't be beat, IMHO!
 
you have em set, should not need changed for a couple of years. Then just minor adjust.
 
I just went out again, 20 miles. They must've been really out because this midget was moving, sounded like a charm.
That SU video was a little hard to follow at first, but I'd have to recommend it now.
Considering I thought it was a head gasket and was two clicks away from the 'buy' button, you guys saved my bacon, taught me a lesson (or two) and got me thinking.
 
Final update, just changed oil and tried my best to find some metal filings of some sort but didn't, put a magnetic drain plug in there just in case, but I'm pretty sure that sump is clean.
There were a few tiny bits in the tranny oil, possibly from my 3rd synchro, but that's another story.
 
Barry, now you can help other folks with SU problems. You are now the local expert.

SUs make her sing.
 
The PO left a video in the trunk "tune your sprite or midget" produced by velocity vision and motorhead. It's from 1990 so I can say if it's still around or not.
It goes through a complete step by step tune up. (I've always FFWD through the SU bit!) but it's a much better tool than a haynes.
 
Back
Top