Low Oil Pressure,Rebuild...
- Thread starter Makdaddymac
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rattling/knocking could be something simple like an exhaust leak I wouldnt assume you have to rebuild the motor. The oil pressure could be directly related to the over heating, the hotter the engine gets, the hotter the oil gets, and the thinner the oil gets. You can do simple checks before you start tearing apart the motor. I would try to figure out the over heating first. See if you are losing coolant, if you are, find out where its going. Do a compression check, if you have too low of compression in a cylinder it MAY be a head gasket, may be something else to, but the more stuff you check the better you can get it pinned down. Also get an aftermarket oil pressure gauge, people always say the stock gauges suck, and to replace them, but the oil pressure gauge in my opinion is the worst and is a MUST to have an aftermarket. I had all kinds of problems with my oil pressure until I changed the gauge and it all went away. I doubt your bearings are shot.
Dont give up just yet man, I told you before I am close to you so I am always down to help if you need something.
Dont give up just yet man, I told you before I am close to you so I am always down to help if you need something.
yeah i know man im sure the gauge is just weirding out. i doubt its the mains to. and the noise could be exhaust related but who knows. as of right now i am going to pin point this overheating stuff like you said. i just don't know why a cold or hot it seems to be losing its balls by the miles.
and besides a leak,which i am also checking for(i know i am not low on coolant) my water pump is new and my thermostat is new(Although this does not mean anything) but i am pretty sure my radiator has had its days and needs to be replaced, i think it is too clogged and causing the overheating issue. my motor was too clean and ran tight before these problems, no sign of smoke or anything...i will fix this. i just really thought i was going to get away with driving a problem free fox....
ps. thanks mob we got to get in touch man, i really would like someone elses help with setting the timing on this car, i dont think i am right,
and besides a leak,which i am also checking for(i know i am not low on coolant) my water pump is new and my thermostat is new(Although this does not mean anything) but i am pretty sure my radiator has had its days and needs to be replaced, i think it is too clogged and causing the overheating issue. my motor was too clean and ran tight before these problems, no sign of smoke or anything...i will fix this. i just really thought i was going to get away with driving a problem free fox....
ps. thanks mob we got to get in touch man, i really would like someone elses help with setting the timing on this car, i dont think i am right,
Are you going by the stock temp gauge or an aftermarket one? The stock ones are poop, but if you don't want to bother installing an aftermarket gauge, at least try swapping out the temperature sending unit (driver's-front area of the intake manifold). Costs less than $10, last I checked. Make sure to use Teflon tape on the threads.
Still running hot? Do a compression test - verify you have good numbers on all 8 cylinders and no low readings to two adjacent cylinders. That'll rule out a head gasket.
Check timing. Roll it back to 10* BTDC (stock) and see if that helps. No? 'Kay. Move on to the next item.
Check your fan clutch. Give it a spin while the engine's at operating temp (and shut off, obviously). It should be fairly stiff and not turn very easily by hand. If it spins freely, it's junk.
Is your air dam in place under the radiator? If not, hit up the junkyard and grab one, or just fabricate one - it's not high-tech, you can make one out of sheet metal or plastic garden edging if you need to.
None of that turn up anything? Buy a 180* thermostat, T-stat housing gasket, some radiator flush, and a couple of gallons of antifreeze. Run the Super Flush crap through there, drain, flush, swap out the T-stat, and refill.
Still overheating? Your radiator is FUBAR - cooling fins are covered with corrosion or the tubes are plugged with junk. Replace with the biggest damned radiator you can cram in there for a fair amount of money, and call it done.
If that doesn't work ... dunno. Call a priest, I guess, and have him perform an exorcism.
Still running hot? Do a compression test - verify you have good numbers on all 8 cylinders and no low readings to two adjacent cylinders. That'll rule out a head gasket.
Check timing. Roll it back to 10* BTDC (stock) and see if that helps. No? 'Kay. Move on to the next item.
Check your fan clutch. Give it a spin while the engine's at operating temp (and shut off, obviously). It should be fairly stiff and not turn very easily by hand. If it spins freely, it's junk.
Is your air dam in place under the radiator? If not, hit up the junkyard and grab one, or just fabricate one - it's not high-tech, you can make one out of sheet metal or plastic garden edging if you need to.
None of that turn up anything? Buy a 180* thermostat, T-stat housing gasket, some radiator flush, and a couple of gallons of antifreeze. Run the Super Flush crap through there, drain, flush, swap out the T-stat, and refill.
Still overheating? Your radiator is FUBAR - cooling fins are covered with corrosion or the tubes are plugged with junk. Replace with the biggest damned radiator you can cram in there for a fair amount of money, and call it done.
If that doesn't work ... dunno. Call a priest, I guess, and have him perform an exorcism.
thanks guys for good responses....i think im going to call the preist first
my money is on fan clutch or clogged radiator. but the rattling/knocking noise only when under load is weird? could this bee related to a clutch not being fully disengaged? the noise sounds like its coming from the rear of the motor/bellhousing area
my money is on fan clutch or clogged radiator. but the rattling/knocking noise only when under load is weird? could this bee related to a clutch not being fully disengaged? the noise sounds like its coming from the rear of the motor/bellhousing area
Tokay,i cant see any leaks but i id loose some coolant(so basically i'm not looking good enough) but also i really don't think my system was completely full, i can never get anything to go into my overflow tank? i have never had any problems filling a system like i have on my 5.0's i either don't put enough or its spews out the overflow tank!!!
also,i warmed the car up and check the fan. it defiantly moves pretty freely, and honestly last time i was paying attention to it i thought to myself that thing spins pretty slow
so basically i am going to do a compression test to make sure im not loosing any coolant internally into the oil
,then a new fan, ((although i could go electric idk. i do have my 3g wiring ready just need an alt...but thats another story)).....
i def. want a new fan and radiator i think the oil pressure is just the gauge.. but who knows...
im just concerned with this overheating. i pray its not a head gasket. i dont feel like tearing this car apart for the 6th time...... im sorry but i will slap a carb on there this time.....
ps. the knocking/rattling...has stoppedi adjusted the clutch with my firewall adjuster and it seems to have gone away and the car is breaking the tires loose from a roll again!?!?!?!
(so basically i'm not looking good enough) but also i really don't think my system was completely full, i can never get anything to go into my overflow tank? i have never had any problems filling a system like i have on my 5.0's i either don't put enough or its spews out the overflow tank!!!also,i warmed the car up and check the fan. it defiantly moves pretty freely, and honestly last time i was paying attention to it i thought to myself that thing spins pretty slow
so basically i am going to do a compression test to make sure im not loosing any coolant internally into the oil
,then a new fan, ((although i could go electric idk. i do have my 3g wiring ready just need an alt...but thats another story)).....i def. want a new fan and radiator
i think the oil pressure is just the gauge.. but who knows...im just concerned with this overheating. i pray its not a head gasket. i dont feel like tearing this car apart for the 6th time...... im sorry but i will slap a carb on there this time.....
ps. the knocking/rattling...has stoppedi adjusted the clutch with my firewall adjuster and it seems to have gone away and the car is breaking the tires loose from a roll again!?!?!?!
my needle starts out fine and then drop to low then to 0....i wouldnt mind if it bounced cause then i know its nothing......
as the overheating its gotta be the fan, i played around it and got to move more air it became harder to turn, the clutch is bad, so i am going to replace it but as of now i drove it and no overheating....
as the overheating its gotta be the fan, i played around it and got to move more air it became harder to turn, the clutch is bad, so i am going to replace it but as of now i drove it and no overheating....
....
The low oil pressure is still probably a consequence of the car running hot (oil loses viscosity as it heats up) and/or possibly a faulty oil pressure gauge sending unit. Really need to just spend a few bucks on a cheap gauge and mount it up under-hood just for testing purposes, if not a permanently-mounted one on the A-pillar or wherever you prefer it in/on the dash. Stock gauges are crap for getting true readings on much of anything. It would help to know exactly how many PSI you're getting for oil pressure before you go declaring your motor toast.
Ditto for the temp gauge - the stocker doesn't give a real reading in degrees, just those ballpark figures of "somewhere between this letter and that letter in the world "NORMAL" that could mean damn near anything. Aftermarket gauges aren't that expensive, unless you WANT a fancy and expensive gauge, and they're not hard at all to mount up. Less than $40 will get you an Autometer triple-gauge set (volt/water/oil) from most parts stores, and they're standard-sized so if you want to later on, you can buy a molded A-pillar mount or something and transfer the gauges into that.
If you're not using quality gauges to obtain reliable measurements, the temp and oil pressure data you're working with is suspect, at best. Get ACCURATE readings first and THEN you'll know where your engine's health stands in those two areas.
A possible reason that you're losing coolant but not really seeing it leak out anywhere is that your coolant overflow tank is probably cracked and that's why it will never stay full. I don't think I've ever seen a single one of those damned things that ever held more than a pint of coolant for longer than 24 hours before it drained out. They always seem to crack along the seams where the two halves of the tank were molded together. You're better off either fabricating one of your own - I've seen some pretty groovy overflow tanks made of Home Depot PVC pipe fittings that you can paint to look nice - or just buying one of those universal overflow tank kits and figuring out a way to mount it up underhood someplace (maybe behind the front bumper or in a fenderwell, if you're really crafty). The leaking overflow tank won't necessarily be causing your overheating problem(s), but if absolutely no other place underhood reveals a visible leak source, that would be the first item I would suspect.
Did you ever do a compression test on the motor to rule out a head gasket issue? (Significantly lower pressure readings in two adjacent cylinders usually indicates a failed head gasket.)
Have you checked the timing yet to verify that it's not over-advanced? (10* BTDC is stock, anything between 10 to 14* is usually pretty safe on most 5.0's.)
EDIT: It might help if this thread were in 5.0 Tech instead of 5.0 Talk.
Ditto for the temp gauge - the stocker doesn't give a real reading in degrees, just those ballpark figures of "somewhere between this letter and that letter in the world "NORMAL" that could mean damn near anything. Aftermarket gauges aren't that expensive, unless you WANT a fancy and expensive gauge, and they're not hard at all to mount up. Less than $40 will get you an Autometer triple-gauge set (volt/water/oil) from most parts stores, and they're standard-sized so if you want to later on, you can buy a molded A-pillar mount or something and transfer the gauges into that.
If you're not using quality gauges to obtain reliable measurements, the temp and oil pressure data you're working with is suspect, at best. Get ACCURATE readings first and THEN you'll know where your engine's health stands in those two areas.
A possible reason that you're losing coolant but not really seeing it leak out anywhere is that your coolant overflow tank is probably cracked and that's why it will never stay full. I don't think I've ever seen a single one of those damned things that ever held more than a pint of coolant for longer than 24 hours before it drained out. They always seem to crack along the seams where the two halves of the tank were molded together. You're better off either fabricating one of your own - I've seen some pretty groovy overflow tanks made of Home Depot PVC pipe fittings that you can paint to look nice - or just buying one of those universal overflow tank kits and figuring out a way to mount it up underhood someplace (maybe behind the front bumper or in a fenderwell, if you're really crafty). The leaking overflow tank won't necessarily be causing your overheating problem(s), but if absolutely no other place underhood reveals a visible leak source, that would be the first item I would suspect.
Did you ever do a compression test on the motor to rule out a head gasket issue? (Significantly lower pressure readings in two adjacent cylinders usually indicates a failed head gasket.)
Have you checked the timing yet to verify that it's not over-advanced? (10* BTDC is stock, anything between 10 to 14* is usually pretty safe on most 5.0's.)
EDIT: It might help if this thread were in 5.0 Tech instead of 5.0 Talk.
once again the oil pressure does not alarm me, it is probably the gauge. i need to get me a oil pressure and temp guage!
i am going to do the following:
check the overflow tank!?!?!
compression test( i will be surprised if this car has a bad head gasket possibly a small crack in the gasket if anything, it does not smoke/steam and the oil does not seem to have any coolant in it)
check the t-stat..
i am going to do the following:
check the overflow tank!?!?!
compression test( i will be surprised if this car has a bad head gasket possibly a small crack in the gasket if anything, it does not smoke/steam and the oil does not seem to have any coolant in it)
check the t-stat..
My 91 has a bunch of miles on it and it starts out at 50psi cold, then drops to 30 psi at idle once it is warmed up (I'm running Autometers), it also gets really hot (as much as 220 with the A/C on while I'm idling), but my radiator needs replacing. Until you get some real gauges on it you won't know for sure. Also, you might try crawling under the car and looking at the bottom of the water pump, mine was doing that when I got it, and it was leaking coolant from the weep hole.
I just finished putting a new rad in my 91 today (Autozone special) and I went from running 205ish with the A/C off to 190. I need to get it out and run it to work on my daily grind, but it seems to cool a lot better. Funny thing is, the new rad was supposed to be a two core aluminum, but it actually is a single core with just one huge tube (looks to be a little over 1"), only down side is plastic tanks.
yeah thats cool. let me know. i was thinking about getting that one two cause its like 95 bucksbut im craiglisting cause of the plastic tanks
ps. what was wrong with that 306? 14.16?wtf???
That was my old car. I sold it a couple of years ago. The power band dropped off at 4800 rpm when it should have pulled to 5800ish (so you can imagine the problem that caused with 4.10's). I think the cats were clogged on it, but I didn't come to that conclusion until after I had gotten rid of it, so technically I'll never know.
So far so good, it creeps up to 195 every once in a while, but falls back to 190 when I get moving again. Way better then the 220 I was seeing before. I was in my WRX all week, so I didn't really get to drive it out and about till today. It also has cooled down a little bit here in Texas, so its not quite an apples to apples comparison. A 25 degree difference is pretty big though.
Go home and change the oil, thats a good way to see if you head gaskets are leaking, figure out what the problem is before you keep changing good parts, its a waste of your time and money. Also take the T-stat out, and put it in a pan on the stovetop with a thermometer and see what temp it opens up at.
If your dropping coolant into the pan it will cause bearing failure, dont drive the car again till you change the oil and see if there is coolant in there. It dosent take much for the bearings to become contaminated
If your dropping coolant into the pan it will cause bearing failure, dont drive the car again till you change the oil and see if there is coolant in there. It dosent take much for the bearings to become contaminated
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