Well more frustration. I just finished a rebuild and attempted to break in this weekend. Posted earlier about the bad starter frying and probably wiping my cam over the weekend. Bought a new starter and no problem. Bam, started right up. I'm five minutes into cam break in and it's sounding okay. Surprised I didn't wipe the cam. Well, then my buddy drops a bottle of ATF while filling the AT. I go to look and foot is wet and slips off the pedal, stall. After 7 minutes, AHHHH. So what the heck, Fire it again and get into cam break in again, still sounds okay with no major misses.

Okay, now the best part. I'm 15 minutes into it and my buddy points out I'm leaking like a stuck pig around the bell housing. Okay I'm thinking, ATF, didn't get my cooler lines tight enough. WRONG, OIL. Pressure still good, started at 70 and after warm-up held at 30 with me at 2 to 2.5 grand. So I continued with the break in for 25 minutes with no major problem except 2 quarts of oil on the ground. I'm thinking I didn't get the intake sealed good enough, valve covers, and oil pan. Wrong, Dry as a bone except around the rear of the pan.

Seems to be pouring out of the bellhousing. OUT of the bell housing where the inspection plate goes. I'm thinking a rear main or a galley plug? Neither of which I installed. I had the machine shop do the lower end. What do you guru's think?

I'm going to take up knitting!

Ken
68 F100 390
74 Bronco 351W

 

Hate to say it but I'd pull the engine back out. If it is the back galley plug either the engine or tranny will have to come out and if it's the rear main it'll be easier than trying to do it in the vehicle. If you pull the distributor out you can drive the oil pump like you did when priming it to see where the leak is.
Sorry for the bad luck.

 

A couple things to check. If you did the oiling mods then you are going to have a good bit of oil up in the heads. Feel around the back of the engine and see if the oil is coming from the valve covers or the rear intake seal. You would be amazed how much oil can come from these areas. Also make for certain that the oil pan gasket is not leaking. More than likely your rear main is out like stated above but check the simple things first.

 

Well good that you got everything fired and broke in. That is a lot of oil for a rear main. It could be the rear main especially if it got installed backwards, but I'd suspect a gallery plug or a combination of all the things mentioned previously. Time for a can of engine cleaner the old trusty water hose and a glass of beer. I always contemplate over a beer, kinda goes with old Ford trucks. You can identify the source of the leak before you start to repair it. Check the easy stuff first, rocker covers, intake manifold, oil pan, gallery plugs and lastly the rear main. These can be done in the truck but it is such a PITA, I'd yank the motor before I'd do it from underneath. Also a good opportunity to inspect the bearings and crank, you know just for grins! Next time, on the engine stand, charge the oil system with a drill. Do this with the intake off and a bolt screwed into the rocker gallery in the cylinder heads. Check all the gallery plugs above the camshaft and at the back of the engine. Don't forget the gallery plug on the left lifter gallery behind the distributor.

 

I am proud to say that the rear manifold is dry and the valve covers are a little moist. I expected the valve covers because I tighten them lightly to about 8 then if any leaks, I tighten as needed. Also, I expected less oil on the rockers because of the restriction I put in. It's just not coming from something that easy, I wish it was. I really wish it was. I am hoping it is the mating surface betwen the rear main and the oil pan. It has to be squirting out on the other side of the inspection plate into the bellhousing. Didn't change much though when I put a little extra torque on the rear pan bolts. Regarding galley plugs, I primed it 3 times secondary to the starter problems and attempting break-in on three different days. Had pressure to 70 and did it for 3 to 5 minutes. If it was a galley plug, it should have leaked then, correct?? Definitley, easiest first. Looked under after lunch today ~18 hours after lubricating the chasis last night and there is only a couple of quarter size drops on the ground. Of course it could be collecting in the bellhousing. Thanks for the the moral and advice

Ken

 

Don't think the oil will collect in the bellhousing unless the truck is parked on an incline. I'd clean around those valve covers and run the engine again. Be sure you have plenty of oil in it 6 quarts. One other thing the side seals for the main cap should be soaked in oil prior to installation. They swell a bit. It is possible that they were installed dry and got oiled when you started the truck and have swollen and solved the problem. I hope so anyway! Let us know how this comes out.

 

Well,

Sorry to say it was the rear main. I took so long because I broke it in for 200 miles first. Heck, the chasis needs lube too! Runs good other than lubricating the road. Pulled it today and pressurized it and the galley plugs were fine. Had to tilt the motor with the leveler and wind it by hand a few times. Sure enough it started to drip off the crank.

It's on the stand and I'm going to hit it this week. Any words of wisdom on the rear main. I have never done one before, that's why I took it to the professionals ?

Thanks
Ken

 

One tip, which is actually a must in my book, is to offset the seal a little from the parting line of the rear main cap. Just leave the seal sticking out of one side of the block about 1/4 to 3/8 of an inch and a corresponding amount on the other side of the cap. Make sure the lip on the seal goes toward the engine and pre-lube it before installing. You'll probably want to loosen all of the mains to help slide the seal into the block. And as William said, pre-soak the side seals. Hope this helps.
Greg
p.s. Is the crank the original or a replacement? Just wondering as there could be some out there with the grooves on the crank (for use with the rope seals) that help direct the oil back into the engine that are cut the other direction for a reverse turning marine (industrial?) application. Not likely, but something to check while you're in there.