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Discussion Starter #1
Well, now that I pulled the transmission and fixed my broken clutch pressure plate, I decided that now was probably the time to fix the engine leaks, especially as it started to leak quite profusely the last time I started it to check the clutch. This car is rapidly becoming a money/time pit.

What I found was at least three separate and very odd (to me at least) issues. As seems to be par for the course with this car, the issues all seem to something other than the normal failure items. First, the plug in the oil gallery for the main bearing located near the front on the passenger side (behind the SPICA pump) appears to be leaking, quite badly. I was going to fix it by removing the pump, drill and pull the plug, and then drill and tap it for an 1/8" pipe plug. I am debating whether to do it to the other good plugs as well.

Second, the front main seal looks like it had been installed crooked, and is also leaking. That is a pretty straight forward repair.

Last, what I thought was a leaking oil seal at the head gasket near #4 exhaust looks like it is actually a leak from the exhaust valve guide. It does not appear to be leaking down the valve stem, but rather around the outer surface of the guide. I guess this would explain why it seems to only leak from there when the car sits and oil drips down the guide and into the exhaust gasket, which was coated in oil. It doesn't look like the guide has slipped, but I won't be able to tell if the guide is loose until I pull the cams. The guide is all covered with cooked on and wet oil. The rest of the port just has a normal layer of carbon. I've never seen that before, but I've not familiar with this engine's peculiarities. I'm guessing that the head will need to come off and the guide at least would need to be replaced. I worry that just trying to seal it would just put off a nasty failure for a bit. I suppose I should just pull the head and have a machinist look at it. What I thought was going to be a quick head gasket job seems to have gotten much more involved. Hopefully it can be fixed without needing a replacement head. The bummer is that this is a big valve head that was installed just 15k miles or so ago. I know who assembled the engine, but I don't know who did the head.

Any comments from the "engine experts"?

Steve
 

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Last, what I thought was a leaking oil seal at the head gasket near #4 exhaust looks like it is actually a leak from the exhaust valve guide. It does not appear to be leaking down the valve stem, but rather around the outer surface of the guide. Steve
You have to rephrase that. That is not possible ! Post a Pic:confused:
 

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Discussion Starter #3 (Edited)
I wouldn't think that it was possible either, and I sincerely hope that isn't the issue, but it sure as heck looks like it. The valve is clean, but the guide is oily and so is the port around the guide and below it.

Here are the pictures. There is a picture of each exhaust port. One and two look good, three is burning some oil, and four is bad. You will see that #4 has a wet black ring around the guide. It is clean before the guide, so the oil is not coming from the cylinder, and the valve and stem are clean. What else could it be?

Steve
 

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Or...The valve guides are shot, allowing oil to pass by the valve stem then get burned in the exhaust port leaving the black coating, the exhaust valves on that year do not have stem seals.

A compression test will not tell you if you have bad guides but will tell if you have blowby from the pistons !
 

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Discussion Starter #6
I am going to do a leakdown test on it as it tells more than a compression test, and as the engine is out of the car I really can't do a compression test easily anyway.

The engine only has 15k or so on it, which looks a bit hard for me to believe, but I saw the receipt. The only smoke that I have ever seen from it was on the first start up of the car when I bought it after it had sat for 9 months without being run. That was one puff, and it hasn't occurred since. It hasn't seemed to have used oil other than what leaked in the last 3k miles, and that wasn't enough to move noticeably on the dipstick. It ran very smoothly and only had Mobil 1 in it since the engine was built.

Tonight I'll do the leakdown, and tomorrow I will pull the head. If there is an issue with the bottom end other than maybe rings, I may part the car, although I doubt that it will come to that. If it just needs some head freshening, I'll get that done and put it all back together this week. I don't have the time or space for this to turn into a major project.

Steve
 

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Qmulus,

It’s possible that new guides were installed and on #4 there was a scratch/gouge in the bore that is now causing the leak. A ham handed extraction on the old guide could easily have this result. If your leak-down test comes up good and the oil usage was not too bad before then I don’t think you have that much down side to driving it. I don’t know what the failure would be for this leak. The exhaust port will gunked up but I don’t see this leading to a failure any time soon or at all (bit of increase back pressure maybe). The bottom end on these engines is quite robust. If you had good oil pressure when it was on the road and no bad noises I wouldn’t think you needn’t worry about the bearings. And as far as oil leaking, if it’s a drop to two on the garage floor/drive way after a drive that’s not too bad for these cars. Good luck with it.

Regards, Al
1967 Duetto (in rehab)
1973 Spider (driver)
1074 GTV (storage)
 

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A leak down test is a good idea. If it is the guide that is leaking you should probably replace it. Guides are under $5 and it's not too tough a job since you already have the motor out. OTOH if it is just leaking around the OD of the guide you might be able to seal it with RTV (on the spring side of course).

It kind of sounds like an amateurish rebuild if it has a bad front seal and guide. Take a little more time and go through the head. I would dismantle the head and clean it and Lap the valves , etc. It's cheap and, you'll know it's done right.

You also mentioned the oil galley plug leak. I don't see how you can drill and tap that without getting into bottom end. You simply must flush the motor of shavings... And yes, do the others while you are at it.

While out you might as well replace the rear seal. Again cheap insurance.
 

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Discussion Starter #9
Qmulus,

It’s possible that new guides were installed and on #4 there was a scratch/gouge in the bore that is now causing the leak. A ham handed extraction on the old guide could easily have this result. If your leak-down test comes up good and the oil usage was not too bad before then I don’t think you have that much down side to driving it. I don’t know what the failure would be for this leak. The exhaust port will gunked up but I don’t see this leading to a failure any time soon or at all (bit of increase back pressure maybe). The bottom end on these engines is quite robust. If you had good oil pressure when it was on the road and no bad noises I wouldn’t think you needn’t worry about the bearings. And as far as oil leaking, if it’s a drop to two on the garage floor/drive way after a drive that’s not too bad for these cars. Good luck with it.

Regards, Al
1967 Duetto (in rehab)
1973 Spider (driver)
1074 GTV (storage)
Al,
Yes, I think the issue with the guide occurred when it was rebuilt. I'll take it to a machine shop this week. Unless the machinist tells me the guides are fine and he would recommend just sealing it, which I doubt, it will probably get new guides. I won't put it back together as is.

The engine ran great, was incredibly smooth at idle and didn't seem to burn oil, but as it did leak a LOT. Not just a drop or two here and there, but Exxon Valdez size puddles lately, requiring me to put a big pan under it. I was on my way to a car wash to clean the engine to check for leaks when my clutch, which had ~3k easy miles on it went, which prompted all this work.

The only noise it has was a strange knock like noise at exactly 2200 RPM. That appears to be a result of cam overlap, as it is loudest with the airbox removed and throttle wide open. It is not load dependent and doesn't vary with engine temp. The cams I have seem to be rather odd, 270 duration and 10.7mm lift with a stamp that looks like a C&B part number, but Colombo and Bariani don't list it. That is something that I will just live with, as it runs very well.

As for the plug, two shops recommended removing the plug and drilling for a pipe plug in situ. If you are careful you can do it getting swarf in the oil galleries.

It appears that the front main seal was not installed straight, so I am guessing that is the problem there, and usual places that leak look OK. Par for the course for me with this car. A lot of the stuff that I thought were great, recent performance engine rebuild, new clutch, etc. have had issues. FWIW, I do have a rear main seal, and "cigarette" seals as well.

I must say this car has been quite a learning experience for me on Alfas. In the few months that I have had it I've had to go into just about everything. I'm not complaining though, I like to learn.
 

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Discussion Starter #10
Update time. The engine and transmission are back in the car is up running and driving again. I'm glad that I removed the engine, as it was much easier to find and repair the leaks with the engine out. If I need to pull the transmission again, I think I will pull it as an assembly with the engine. Going in was a piece of cake.

So, now for the oil leak repairs... The three oil plugs on the side of the block were drilled out and 1/8" stainless pipe plugs went in. This was a pretty easy job, although tedious with cleaning the bits and tap of grease and cuttings after each pass. Only the front plug was really leaking (and was VERY loose), but I did them all. With care, I got NO junk into the passages, and actually cleaned out some very old crud where the plugs were.

The front pulley seal was leaking as it was pushed in too far and crooked. That was a quick replacement and I cleaned and polished out the wear marks on the pulley. The new seal now seals very well.

The SPICA pump mount to the front cover was another leak, as there were two gaskets, one of which was coated with gray RTV which was almost completely blocking the oil return from the pump. I used a new Viton O ring and used engine case sealer with no gasket. Works great on modern cars, and seals great on this one too.

I also found the dipstick tube pipe that was originally sealed into the block was loose. (The dipstick goes into the block on my car, not the pan like earlier cars.) On that I used permanent "Bearing and Stud Retainer". It is sealed and won't come out again.

The large plugs on the back of the head were also leaking. On these I used a liberal coat of anti seize compound and tightened them up. They appear to have been put in dry in the past.

As for the head, I decided not to pull it. I believe the oil in exhaust ports 3 & 4 was the result of parking on a hill nose up. The oil ran to the back of the head, and was able to leak down the valve stems. I could have pulled the head and had new guides with stem seals put in, but as the car doesn't burn oil, I decided not to create more work. I'll leave that for next spring if it really bothers me.

I just finished with all the "while I am there" issues today, and took it for a nice long drive. I am happy to report that it hasn't leaked a bit and it is now all ready for summer. Hooray!
 

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I used to own a FWD car that would blow horrific smoke at start up- caused by valve stem seals leaking on the exhaust side only when parked nose down. I figured out what it was and just avoided parking nose down hill. Oil usage was never a problem and the combustion chambers cleaned up after I reduced my downhill parking too.
One of those thing you have to weigh up on older cars, cost versus result.
 
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