New engine for my F-600 Dump Truck

[Egon]

Eddie, have you tried running it with PVC valve disconnected and plugged at the carb?

Actually why not take off the valve covers and start it up. See what happens.

I'm thinking that oil may not be draining back to the crankcase properly. This lets more than usuall amount of vapours back to the intake manifold fouling the plugs.

Diesel in gasoline usually makes a lot blue smoke and then shuts down.

Note: A disclaimer to any accuracy of my statements as my past record has not been good!

 

[Wayne County Hose]

White smoke is coolant or ATF. Since you have a clutch, I don't think it's ATF. Get a radiator pressure tester and hook it up. Do a leakdown test. If it passes, start the truck with the gauge still on the radiator. Monitor it, let it warm up. If the gauge tries going over 8 lbs, release the pressure. When the engine is warm, pump it up to 12 lbs and check the exhaust, if the smoke gets worse, there you go, coolant getting into the fuel/exhaust system. Could be a crack from the exhaust seat to the coolant passage which would not make the spark plugs turn color. This is common on some engines with the 2 middle exhaust valves together. I haven't read the whole thread, which engine do you have, 366?

 

[EddieWalker]

...which engine do you have, 366?

The engine is a big block 370, which is very similar to the 460 with allot of interchangable parts.

I haven't tested the radiator since I haven't lost any water at all. It does seem likely that it could cause the smoke since the intake manifold carries water through it, but I go back to the oil on the spark plugs. How do all 8 spark plugs get covered in black oil?

Iron Horse,

Diesel in the fuel is possible. I'll buy some gasoline today and run a fuel line from it to see if that changes anything.

Egon,

I haven't tried that combination of taking off the PVC and plugging the carb vacume line. I looked in the PVC hose for any sign of oil and didn't see any, but I could have missed it. I'll try this and see if anything changes.

I have a new set of valve cover gastkets, and I'm looking forward to taking off the covers to see what I can figure out. I remember in high school that we had a car with plugged drain lines in the heads. It was an older car with alllot of miles on it. I cleaned them out and solved the problem, but I can't remember what the problem was. I don't remember smoke being an issue.

Eddie

 

[Wayne County Hose]

Oops, 366, I was thinking Chevy truck engine. Your engine is a Lima series Ford, similar to mine in the pic. It doesn't take much coolant at all to make a lot of smoke. But the oil, on all the plugs. Follow all of your vacuum lines, do they go anywhere where there is ATF or power steering fluid, or any other type of oil? I have seen modulators leak ATF into an engine's intake and make white smoke, this is common on Chevys with automatic trannys. I'm going to go back thru the posts and see what info I can find.

What Iron Horse says makes sense and is worth a shot. If your air filter was plugged, vacuum would be high. Usually if a diaphragm type fuel pump is going to leak, it will leak fuel into the oil, not the other way around.

I would also check the vacuum line to the distributor's advance diaphragm. Usually if there is oil in the intake passages, there will also be oil there.

 

[Eagleview]

Eddie ,
While your at the truck have a look at the exhausts to make sure one is not blocked with mud . I was thinking maybe you backed into a pile of dirt and stuffed a pipe with dirt which will also cause your symptoms as the gasses from one bank will have to go through the crossover passage in the intake manifold to exit out the other pipe and will cause eccessive crankcase pressure . Then i remembered your thread about the lake eating your truck . Have a look at where the pipes are ....... Also i was thinking your truck cab looked familliar and now i know why , it's the same as my 96 F250 project truck .

 

[EddieWalker]

Iron Horse,

I think you figured it out when you mentioned the intake manifold. I took it off today and every intake port is full of oil. The gasket has three layers. One is the sivler pan that conects both sides of the engine. Then at the haed, there is another metal gasket on either side of the silver one.

When I installed it, I put silicone on either side of the gasket, but not bewtween the layers. I couldn't find an obvious leak, but this migth be where it's at. I'm debating on not even using the gasket and just using silicone. Has anybody done this before?

While cleaning off the old silicone, I noted that there was oil in the very middle port. I thought this was for water, but it's full of oil. The water ports at the beginning and end of the mainfold have water in them, but this one has oil, as you can see in the picture. It connects to both heads and has a large cavity right under the carburator. Why? What does it do?

I'm not sure if the gasket is leaking, there is one or two places where it might be, but with that big pan underneath the intake manifold, I'm not so sure it's coming through the gaskets. The vacume test says the gasket wasn't leaking, I can't find any sing of leakage, so now what?

Thank you,
Eddie

 

[Eagleview]

The one in the middle is the exhaust crossover port i spoke of . It is there to heat the intake charge . That's what i meant about if one muffler was blocked on a twin system the gases have to travel through this port to be able to exit the other exhaust pipe . If the gasket is blown at these ports it will presurise the engine with exhaust gases . The tin pan stops the hot oil being flung at the underside of the intake manifold by the camshaft . Make sure to replace all gaskets (Felpro would be my choice) re-use the tin plate shield . Use Neutral cure Silicone on the valley ends but not on the intake ports . Petrol vapour travelling past the Silicone will make it fail in short order (use Permatex or simillar). Scrunch up a handfull of Aluminium foil and lightly hammer it into a plug shape and force it into the center exhaust crossover ports in the heads , use the wooden handle of a hammer to make it a flush fit . This will stop the exhaust over heating the carb and causing vapour lock on hot days . Make sure to check the mufflers for mud before starting the engine . I think your engine is fine , just check the things mentioned and put it back together .

 

[TCBoomer]

Here's my thoughts Eddie...

Were the heads surfaced? And if so, do you know how much was removed? Reason being is that if they were done in then past by a previous owner and then again by you, there may be a mismatch with the angle between then intake and cyl heads, which could allow oil to be sucked up from the lifter valley. Usually with worse cases, you will have driveability issues right from start up of the fresh overhaul. This might not be the cause and may be a long shot, but was worth mentioning.

A more likely cause would be the silicone sealer on the gasket. All intake gskts should be installed dry, no sealer. And NO do not use just a sealer in place of a gskt. Only the end rails should have a sealant applied. What may have happened is since the intake is alum, the expansion/contraction between the intake and iron cyl heads caused the silicone seal to break which again could suck up oil from the valley or even past the threads from the intake bolts. Are the holes in the cyl head for the intake bolts blind or open? If open, oil could be sucked up past the threads.

Here's what I would do as long as the heads haven't been surfaced multiple times. Replace the intake gskts including the valley pan with new. It should be part of an intake gskt kit anyway. Unless your having specific vapor lock issues, I wouldn't block off the exh crossover ports. Majority of the time that tin valley plate is sufficient to keep hot oil off the bottom of the intake and keep the temperature within limits. If you are having vapor lock problems, they make a gskt kit...last time I checked...that has those ports blocked off for that purpose. Only use an RTV sealer on the end rails and around the coolant ports. If the intake bolt holes are open and not blind, use a teflon sealer on the bolt threads. DON"T use the teflon tape, use the sealer in a tube.

Good luck

 

[Wayne County Hose]

Eddie,

Iron Horse is right on. The aluminum tub below the intake is called a turkey tray. You can re-use it. Use Fel-pro gaskets, they are made to be used without any sealer. Just put a dab of silicone in the corners where the intake, heads, and block meet. The exhaust crossover can be blocked. This is there to help the engine warm up faster in colder climates. I don't think this is necessary in Texas. Head surfacing will not create an angular mismatch. Port mismatch yes, but on a truck engine, nothing to worry about. If you look up Summit or Jeg's you can find heat riser block-off's to block those exhaust passages. I've never tried the aluminum foil trick. I don't know about the oil in the intake manifold crossover. You naturally get some builup of carbon or if you are burning oil, some sludge buildup, but oil? Weird. If every intake port is full of oil, I believe you are sucking it in thru the vacuum system somewhere. That's where I think your problem is. There are no oil passages thru the intake gaskets to leak. All the oil goes to the top of the engine thru the pushrods.

 

[EddieWalker]

The exhaust is clear. Both pipes join into one just before the muffler. One of the things that happens from time to time is the muffler will come off at the point where the two pipes join into one. This just happened and I re-attached it again. Kind of an ongoing problem since putting the engine back in, but I don't think the source of this problem.

Thanks for the information on the crossover vents. I never heard of such a thing, but it's good to know. Now that I know there's a sourse of oil that should be there, I think it will lead to how I'm getting oil into the fuel/air part of the manifold. It makes sense to me that the problem is in that area.

The heads were fine and not milled down. I do not know if the engine has been rebuilt before, but there was no sign of it that was obvious. I think the heads are original and of the proper height. I could be wrong, but don't know how to test this with them on the block.

The bolts might be another, or the main problem. When I took it apart, I just put the bolts into a coffee can and set them aside. When I put it back together, I realized that the bolts were different. All were 9/16 head, but the head design and threads were different. I thought I put them in the right place, but now that I've taken off the intake manifold, I have my doubts.

If the wrong bolts were used, either not long enough, or without the proper head design, could this allow oil to get past the threads? Could enough oil get through to cause my oil issues, but be small enough to give me a solid vacume test? I'm going to buy new bolts and use teflon thread sealant.

The owner of the machine shop where the work was done on the block said that the intake manifolds on those engines have a history of leaking. He said to put on silicone, then let it dry before installing the gasket. Now that the gasket is off, I need to talk to him again and show him the gasket, because it's not what I was expecting. I didn't remember it being three pieces. The metal pan, and the two metal gaskets on either side of the metal pan.

The intake manifold is cast iron, not aluminum.

I might just put it back together with new gaskets and bolts, but hopefully do a better job of sealing everything up, and hope for the best. I hate not finding the problem and knowing for sure where it is.

Could the manifold be cracked and allow oil into the fuel/air passage, but be so small as to not affect the vacume test? I find this hard to believe, but I'm grasping at anything right now.

Thank you,
Eddie