Just got back from the Primer Nats, and I went through almost 2 gallons of oil down and back. I checked the oil, its fine, drive for about 30 mins and the pressure starts to steadily drop over the 30 mins. On the highway, it reads about 9-14 psi. Once I pull off, it drops to 0. I shut off the motor, check oil, barely reading on stick. FIll back up, pressure bumps back up to about 20-ish, and it stays that way for a while. Then starts to drop as its leaking. When I stop to put oil in, theres a slight oil trail behind the car, and a puddle starts to form below the oil pan breather. When its cold, i noticed it has WILD pressure spikes. It fires up and idles when its cold at about 60-70psi. Then when I start driving it, for a few minutes it will drop to 20, then back up to 60, then to 30, then to 60. Over and over like that. Then when its warm, it sits at about 20, until it starts leaking bad. I dont know, im stumped. Could a pinched oil line to the filter cause this? My lines are OK, but one bend is real tight. It still pumps oil into the filter can. Ive checked it before. But maybe its causing pressure below?
Oh ya, checked the compresstion today. All were 65-70, and number 5 was 85psi. Pretty low. Is a rebuild in my NEAR future? Dipstick tube is correct, just measure it. And, its leaking also... great. Also, just noticed a decent amount of oil coming from around the header flanges.
Yes It is. Cylinders should be at least 100psi. I've had quite a few of those dip stick tubes leak. Easy fix with the pan remove but doesnt at all relate to your problem. You have to be blowing oil badly out the exhaust when you drive. It a wonder your plugs aren't fouling....You need a rebuild.
I didn't read the whole post...but I am going to guess that the oil line for the oil filter is cracked/broken, check the flared ends.
OK your dip stick tube is the correct length, how about the dip stick The correct one measures 16 5/8" from the top of the curl to the bottom of the stick. It measures 14" from the **** washer to the end of the dip stick. Low compression only means soft rings or valves., no compression would indicate cracked piston. What are the measurements of your dip stick?
Or...just drain the thing and checkitout after dumping 4 quarts in...a bit low but entirely survivable. I think DS is tracking right here...you have something odd somewhere. The compression is low, but not in the blowing oil all over the map category! I too think this is some oddity of ***embly, filling, damaged part...I do not think this is ring failure, the problems are out of proportion.
Ill measure the stick when I get home. I recently had the pan off, and tried my DAMNDEST to get the pan bolt off, to no avail. I even put heat to it but it wouldnt budge... Im missing something then i guess. I dont understand how I can have TOO MUCH oil in my car when the pressure is fine and shows OK on the stick. Then the pressure drops and I check my stick and theres nothing on it. How would this indicate too much oil? Hey, I appreciate all of your input. Maybe after we figure out my leaking issue, we can tackle the retarded timing issue? Man, im over it. This car is making me feel dumber and dumber every day I own it...
What if the clearance from the oil sump screen to the bottom of the pan was too little, i.e. dented pan or misinstalled pump.?? The oil pressure would be fine at idle and would get high when running but it would pump out of the block and everywhere else if it couldnt pick up "new" oil from the bottom of the pan. hence when you come to idle there is no oil left and no pressure. I have been experimenting with crack lately so this may be waayyyy wrong but just an idea
My dipstick tube measures 13 13/16 from **** to tip. The Drain plug is stuck in the pan and i cant get it to budge. I put heat to it and it when I just had id off and it still wouldnt move. Is it normal to have pressure swings while driving down the road and going around corners?
This is one of those situations where a guy wishes he had a clear plastic oil pan so you could see what is going on in there while it's running. If the oil pump had a pressure leak jetting oil on the breather or maybe a bearing with a little too much play that's letting oil by near the breather I don't know. It's loosing oil pressure from somewhere or you would get a better pressure indication than you are. Too much oil sloshing up into the cylinders can wash out rings on some engines actually causing lower compression without causing it to burn excessive oil. They will eventually start burning more oil though if this persists. Usually a bad rod bearing will start knocking pretty quick so it's likely something else. Airplane engines have an oil temperature gauge that helps determine if too much friction is taking place. You don't have that option. If its blowing it out as fast as you mentioned then it might not have a chance to get hot. If a sludge tube was leaking but not gushing to the point of total pressure loss that also might be a possibility. You have a good head scratcher here for sure. It might take some internal investigation to sort this one out. Hail to the Hot Rod God and flathead Demons be gone!
Ya, im about to just tear into it and see if I see anything wrong. I called H and H today, just to ask what they thought. Right off the bat, I could tell they get A LOT of calls! The dude on the other end sounded a bit annoyed! Anyways, i told him my problem and we tried to diagnose it. Just like we have determined, its overpressurized somewhere? Who friggin knows. Maybe ill just pull it and put a nailhead in it?
If your hole is open, where your fuel pump stand is, it shouldn't be pressuring up the crankcase. Granted rou might be getting dirt or whatever in through the open hole but it would allow crankcase pressure to vent anyway. You may have something partially blocking the oil pump pick up screen that could cause oil pressure loss. Folks who take the fuel pump push rod out in favor of an electric pump can experience a loss of oil pressure in the push rod bushing area if it is not closed off. I remember watching mechanics pressure up the oil system with an external oil pump & reservoir to prime the oil system and make sure oil was exiting in all the right places. This was done with the oil pan off so they could see leak down from each connecting rod and main bearing as well as the cam bearings. The pressure was applied where the sending unit tap goes. I haven't seen anyone do this in many years but a guy could tell if there is an internal leak from a crankshaft sludge trap or excessive loss p***ed a particular bearing or what not. If you remove your pan (probably for the umteenth time right) you will get a chance to remove your drain plug. You might have to destroy it to keep from doing further damage to your pan ie cut or drill & cut it into pieces for forcefull extraction. You may be able to find out how or why the oil is rapidly exiting your motor just by careful inspection of everything in there. You can drill out the rivets to your dip stick tube support & make a new gasket. Just use screws with a good positive self locking type nuts to replace the rivets. Seal everything with RTV to prevent further leaks. Don't get discouraged from your experience. The flathead is the simplest motor around but even with that you can still get some complicated problems that take time and some help to sort out.
ROTO-Thanks for the advice. Its just extremely frustrating to have to tear into this thing, AGAIN! I just had the oil pump screen off and cleaned it while it was out. Maybe I can pull the intake and take a look around.
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