several issues

[albersj51]

A couple of weeks ago i changed the oil (20w50) and i started getting this purcolating sound in the engine. Pull the oil cap off and you can hear it in there. oil level is good and the oil pressure light isn't coming on, so pressure should be good. Friend thinks its just the oil circulating (hope so!).

i drove it up last week to get a new battery and she felt a little sluggish.

Drove her tonight and running about 45mph steady with steady light throttle she stumbled a little, nothing major, but enough to make me turn around. Turn her off and she diesels like crazy for a few seconds. Open the hoods and see some smoke coming out of the valve cover breather, nothing major just a little. Gave her a few minutes and she started right up. Buddy thinks my weber 34ich needs a rebuild.

Its a 67 2A, 2.25L PETROL, new pertronix ignition, new pertronix coil, new exhaust manifold, electric fuel pump.

Any thoughts? Are all these connected? Timing was done with a timing light and is spot on. Heard Landies can be out of time even when the light says it is. Maybe that's the stumble/dieseling? What's the purcolatig noise?

As always, thank you for any and all help!

J

[stomper]

A lot of people prefer to time by ear, as the timing marks were set up prior to the reformulation of gasoline, and the elimination of lead in the mixture. Also, the timing recommended in the green bible was for an original engine, and if the carb has been changed, the best setting for your vehicle may be different than the books recommendations.

Poor timing will cause a loss of power and deiseling, but I do not know anything about your oil gurgling issues.

[albersj51]

Thanks! Ill try timing her by ear and see what that does.

Anyone have an opinion on the oil gurgling?

[disco2hse]

Hearing the oil slosh around??? Jeeze I wish mine was running that quiet! You'd have to have Niagra running through the engine to hear the oil in mine. Otherwise:

Open the hoods and see some smoke coming out of the valve cover breather, nothing major just a little.

• Valves burnt or out of time, so possibly cam shaft or timing chain too slack/worn, so possibly guides are worn.
• Blown head gasket.
• Rings need replacing
• Re-bore required

[albersj51]

But why would this suddenly happen after i changed the oil? If it were a major fault (head gasket, worn chain, rings, etc) wouldn't take have been there before the oil change?

[disco2hse]

There may or may not be a causal relationship between your actions and what is going on. It is not relevant to what is required to execute a repair. Maybe a problem did exist previously but you just never noticed. Maybe the old oil was so full of sludge that it masked loose or worn components. Maybe the oil used previously had additives to do the same (like Wynns tune-up in a can). Maybe the previous oil change used a more viscous grade, to do the same.

Any guess at what is going on can only be supposition until you get a pressure test done.

What colour is the oil now?

Is it black and sooty/cloudy/...?

[albersj51]

The oil looks good and clean, no soot or milky substances. As for the old oil, it looked horrid...nice and black.

A buddy of mine is digging out his compression tester, as soon as he gets it to me ill post the results.

[badvibes]

How many miles on the truck since the oil change?
Do you run a spin on oil filter adapter?
What pressure reading are you getting for the oil since the oil change?

Jeff

[Rineheitzgabot]

Did you fill it with too much oil?

[Terrys]

Did you fill it with too much oil?

I was wondering that also.

[albersj51]

Probably no more than 30 miles since the oil change. Not running the spin on, just the old fashion original type.

As far as pressure, don't know as my truck lacks an oil pressure gauge

I thought i either over or under filled, too, but its on the money just below the H

[Tim Smith]

To be honest, it sounds like you are getting blow by. Smoke from the valve cover breather and super dark oil leads me to think that compression is blowing by either at the rings or the valves.

The fact that you are dieseling on shut down is either a sign you are running too advanced or too lean and the engine is developing hot spots. If you've been running like this for a while, you could be getting premature carbon build up on the rings or valves which would kind of add up to your description. Webers don't really adjust much so if you don't have a clogged jet then your jets might be incorrectly sized for your elevation. Sounds like your ignition is close enough that it shouldn't be causing trouble but you can always retard it more if that helps.

If you are worried about clogs in the oil passages, you can always run the engine with the valve cover off and watch the flow of oil to make sure nothing is clogged up at the valve train. Don't rev it up without the cover unless you want oil all over the place. I doubt you will find anything wrong but if you shut it down a couple of times you might get lucky and see bubbles which could give you something to look into.

Fixing carbon build up:
If you do have carbon build up, you may get lucky with a little marvel mystery oil. The trick is to get the truck up to operating temperature or even a little hotter than normal. Once it's hot, you can pull the vacuum line at the distributor and stick it into your jar of MMO. You should see lots of smoke out the tail pipe which is just the MMO burning poorly. Don't worry about that too much and proceed to rev the engine well through the range. Feel free to empty the jar of MMO in this fashion and if you are lucky, you should be able to burn off the carbon from the top end. If you like, I hear Sea Foam works well for this as well. Even water works but you could hydraulic your engine if you don't know what you are doing so handle water with care.

If you are still getting blow by at this point it will likely be from the rings. If that's the case, don't start planning your bottom end rebuild just yet. Instead, you can drop a quart of MMO in your crank case for at least 500 miles before your next oil change. Drive it like you stole it and if you can, try to get a few highway runs in. The objective here is to clean the bottom end and if you are lucky you may be able to clean the carbon from the rings without a full on rebuild.

No I don't work for Marvel Mystery Oil. I figured this out after getting similar issues as you are describing. In fact, my compression was down right terrible and I would have a hard time keeping the engine bay clean from all of the oily smoke coming from the breather caps. I thought the engine was shot and as a last resort I started experimenting with MMO. That was about a year ago and I'm still impressed with how well this engine is running.

It worked for me, it was cheap to try and it's kind of fun to try but YMMV. Either way, you really can't hurt anything so long as you don't dump tons of fluid straight into the carb and hydraulic it.

[shock]

Although this article is for an MGA it touches on general issues for engines that are dieseling.

I've been having the same trouble with my 88 but it has a Chevy L6. No idea if it is helping yet but I'm trying a higher octane gas and I did a seafoam treatment this past Saturday. It wasn't dieseling after that but I may not have had the engine hot enough and I haven't taken it out since.

[disco2hse]

You would only have an indication of an engine `dieseling' if there were traces of fuel in the oil in the crankcase. This has not been reported and frankly, if it were the case on a petrol engine then the engine is probably rooted, or at least will require a rebuild to remove the glaze from the cylinders and any trace of fuel and contaminated oil from the galleries. As Tim said, it is more likely to be the spark that is too advanced.

But. The points that Tim made are the same as those that I made and your best course of action is to test before you go and bugger anything up and get some diagnostics done. Blow by on an old engine is not normally anything to get worked up about, in fact there are few engines that don't once they've done over a couple of hundred thousand kilometres.

So. Get your pressure test done. Differences in pressure when oil is added if the pressure is too low will tell you if the rings are shot, or if it is the valves. I think you can probably rule out a head gasket, but not necessarily since it may be leaking between cylinders or valve guides.

Oh. Do you get smoke billowing from the exhaust when you start up? What about when you accelerate? What colour is it? Does the smoke go away when you are running at constant revs? These are indications of possible burnt or unseating valves, shot rings, head gasket issues, etc.

[albersj51]

Thanks for the info everyone. Rented a compression tester, which turned out to be broken (get what you pay for = free). Ill get another and try again.

Plugs looked ok, but smelled like gas...so in assuming its running rich.

As for billowing smoke from the exhaust, no. There is some blue, but it wasn't heavy and it seems to go away when you rev the engine. Im thinking blow-by from the valves, but we'll see what the compression test says.

Thanks again for the input.

J