Oil pressure dropped

[patmckinneyracing]

If the rings are done, then that means that the piston chambers probably have a ridge that needs to get bored out. Which then means new pistons. The subtle knock, you couldn't hear it unless you were really, and I mean really, listening for it. The only reason I noticed it is cause I built the car and can tell when the slightest change occurs, which I'm sure most of us can do anyway with our cars.

On top of any engine expenses, I still have to get the 700r4 rebuilt to hold 400hp/450lb. Then tear out my carpet because I have 3 massive holes in my floors from an exploded driveshaft.

The reason I'm leaning towards the roadrunner is because I'm kinda fed up with the malibu right now. It never started having problems until I had to drive it for 3 hours on back road highways to get to college. Even then, after swapping to highway gears and babying it, I had to fix something every weekend when all the stupid parts were new. I'm sure you guys have had the same feeling at some point with one of your projects.

Yes I do all my own bodywork, paint, engine builds, etc. Only thing I can't do is any machining. The point to roadrunner is to gather up parts now so that when we do start, everything is there.

What will be the deciding factor is if I pop that oil pan and the crank is ok and the piston chambers and rings look good. If they don't, and I have to do a full rebuild on this engine, then it is going to sit. It really sucks to put over 5 years of effort into building a car and having the ONE AND ONLY stock piece of the drivetrain, the driveshaft, to give out when it never showed any issues. I had sandblasted that thing down the weekend before and it was solid as could be, didn't think I had to magnaflux the damn thing. Frustration is the evil red eyed monster that will kill us all.

 

[Doober]

Have you tried changing the oil yet to see what happens with pressure? Baby steps, young grasshopper.

 

[gto78]

Have you tried changing the oil yet to see what happens with pressure? Baby steps, young grasshopper.

Exactly my thoughts as well. I'd have changed the oil right away just to answer that question and possibly avoid bigger expenses. I've had oil pressure problems in the past. The engine would start with normal high oil pressure (60-70 at idle) and after it warmed up it would drop to less than 5 at idle, and barely 40 while driving. Basically the main bearings being shot will kill your oil pressure, and rod bearings being shot will make lots of noise but not affect your oil pressure as badly.

I've been broke and desperate enough to replace all my main and rod bearings in the parking lot where I went to college, without removing the engine or crank etc. I needed to get to school and work every day, and had very little money. There wasn't any way of measuring the main journals while installed in the engine, so I took a chance and just replaced the bearings, hoping the clearances weren't too far out. I polished the crank with a light emery cloth. Put it all together and it lasted another year before making noise & losing pressure again.

It's not to hard to replace main bearings while installed in the engine. If you can remove the oil pan, and if you can remove the main caps (1 at a time obviously) then you can replace the bearings. I can't speak for all engines, but I know on my Pontiac I had no problems using a cotter pin to spin out the bearings. You use a large cotter pin that is inserted into the oil hole in the crank journal of each bearing location. The part of the cotter pin sticking out will need to be reshaped/flattened so that it's the same thickness as the bearing, then just rotate the crank by hand and it will literally spin the bearing out of the engine. It's important you turn the correct direction since the bearing has a lock on one end that normally keeps it from spinning. If you've already spun a bearing from driving with low pressure/excessive clearance than the cranks gonna be shot anyways, so no bearing change would help. I was able to do the whole job in one day, and in my case the oil pan doesn't just pop off, you have to raise the engine about 4 inches/unbolt the engine mounts etc. for the pan to come off.

 

[pontiacgp]

first off 260 to 280 really isn't overheating the engine...we've hit 260 + in our race engine on numerous occasions and it's just a performance 350 crate, nothing special. I doubt you have damaged anything internal if the oil and engine was in good shape. I run amsoil synthetic in my cars and I overheated my old 305 a few times and the oil never let me down and probably saved that engine. I'd change the oil with some good synthetic and a good filter and see what happens

 

[patmckinneyracing]

I'll try that next then. Problem is when I tried to start it something in the transmission got destroyed when the driveshaft snapped cause it sounds like a can of metal being shook up when I try to start it. Either my torque converter is done or the internals are thrashed.

 

[Doober]

If the driveshaft was shoved forward when it blew up it's very possible it broke something internally, that's why they say having enough travel on the slip yoke is crucial.

 

[patmckinneyracing]

It was only on half way and had plenty of space but it was very hard to put that driveshaft back in that last time and the output shaft did have a very slight bit of play in it.

 

[DRIVEN]

If this is a daily driver that has to get you to school and back, you may want to consider a stock (cheap) 305/350 and a TH350 since you have highway gears in it anyway. That would get you back in the road fastest for the least amount of money. I'd be surprised if you can't find an engine, transmission and stock driveline for under $300. Then you can either go through the engine you have and investigate your transmission problems at your leisure or move directly to your Mopar. When you get ready to swap back you'll probably get every penny back when you sell the replacement stuff.
...or you could just buy a Honda :lol: .

BTW, if you tear into the engine you have, don't forget the cam bearings. SBCs direct oil to the cam first. If those bearings are shot it doesn't matter how fresh your crank/bearings are.

 

[patmckinneyracing]

Its not a daily driver. Thats why I bought my dakota in my sig.

 

[DRIVEN]

The reason I'm leaning towards the roadrunner is because I'm kinda fed up with the malibu right now. It never started having problems until I had to drive it for 3 hours on back road highways to get to college. Even then, after swapping to highway gears and babying it, I had to fix something every weekend when all the stupid parts were new. I'm sure you guys have had the same feeling at some point with one of your projects.

My mistake.