Hi. I bought a 1990 D150 wth 135,000 original kilometers on it. So far all I've done to it is give it a coolant flush, and replaced the radiator cap.

When I drive the truck for a little while (about say 15 minutes??) the red oil light starts to flicker on. And then comes on completely. What would be causing this and how do I fix it. I don't know much about cars in general.

Thanks for any help!!

 

Hopefully it's the sending unit for the light. If not you're in trouble,the main/rod/cam brgs. are probably shot. It's also possible it's the oil pump or the pressure releif is malfunctioning,but not likely.

On a 318/360 engine the sender is located at the top rear of the engine, next to the distributor. On a slant 6 it's on the lower right side of the engine. You'll also need a special socket to remove/install it with.

My Dakota was parked by the previous owner because he thought it had issues with the oil pressure. Replaced the sender and it's fine. With any luck yours is too.

 

Thanks. It's a 318 engine. Is it possible that f the truck hasn't had a simple oil change in AGES that this would cause the light to come on? The previous owner only drove it to the dump 4 times a year. I don't think she ever did routine maintenance on it.

Also, how much should a new sender cost me? I'm off work and completely broke so I'm guessing the wreckers is the place to go to get a used one??

Also is white smoke out the exhaust possibly connected to low oil pressure??

Thanks again.

 

well if the white smoke goes away when the car heats up then it probably isnt a big deal.

did the truck sit? antifreeze can break down leaving the water to rust out the channels through the block, but also to thaw and freeze in the gaskets, causing warping, cracking, and all those nasties. So that could be an issue. Its good that you did a flush though, now try adding some Bars Leak to seal up any minor cracks. A big coolant leak (cracked head, for example) is like a cloud factory in your tailpipe. you'd know if its serious.

Usually an oil leak comes out the tailpipe bluish, not white. you can also smell it, versus a coolant leak, which might evne smell a bit sweet. Another thing is that that oil leaks leave an oily residue if you put your hand in the exhaust, and coolant leaks leave a wet-ish, but not really oily feel. Make sure the engine is hot when you check though, since water (well, steam really) in the exhaust is normal untill it heats up.

good luck!

 

Honestly, no offense intended, but it sounds like you bought a turd. On the oil it could go either way, if it's thin as water it could give low pressure, if not sounds like the motor is just worn out from lack of proper maitenance. Hence the smoke. [If it is smoke and not steam]The sender is about $7.00 American, takes a special socket to fit it. Tell 'em you have a light and not a gauge. With some cussing you can probably unscrew it with some channel lock pliers. Try the sender first.

If the sender/oil change doesn't do it and the light only comes on at idle you can probably drive it with care. If the motor ain't knocking or rattling it should live a little while yet. I wouldn't take any road trips in it. Put some 20w40 in it and a bottle or two of STP or Lucas oil treatment. It might be a real pain in the *** to crank when cold though unless it came equipped with a block heater. If not, a heat lamp next to the oil pan might help.

 

hey just noticed youre canadian. me too, about 45 minutes east of toronto in whitby, good to have you aboard.

 

Thanks for the help. The smoke only comes out one tail pipe. The other pipe (on the dual exhaust) produces hardly any visible smoke at all even in cold weather.

Would an external coolant leak cause the smoke? Or is it only an internal leak that would cause it? because i have found an external coolant leak although I cant pinpoint it. Im thinking a possible upper radiator hose hole at this point. There was coolant on the battery and on other side of motor (like it had been spraying).

I'm trying not to jump to conclusions that it's a major repair issue, since I always do that. And as a result have over reacted to car repairs in the past. So Im hoping the head gaskets aren't blown and so forth, and that it's just a pile of small repairs adding up.

 

Could be sludge blocking the pick up screen. If changing the sending unit and oil don't help. You could drop the pan and check before you throw in the towel.

 

All the engine's symptoms would be a big help. Blowing water out the tailpipe with a funky smell? If the radiator smells gassy like burnt exhaust, or there's milky sludge on the oil cap,milky oil, or the radiator pressures up almost immediately, or it blows water outta the radiator after running a while then chances are you also have a cracked or warped head and/or blown head gskt, or all three. If it's been allowed to freeze a split in the cylinder wall is also possible.

Pull the spark plugs and look for water on a plug or 2 plugs adjacent. Or oily plugs if you think it's smoke not steam.

One other thought, the steam on one pipe when cold can mean nothing if the heat riser flapper is still on the exhaust manifold. It's closed when cold to promote faster heating of the intake manifold. Takes longer on that side to boil away condensation.

 

Someone in this thread mentoned the coolant can break down over time and then cause rust etc.

Well before I changed the coolant I had checked the strength and it was only good to -19 celcius. Where as it should be good to -35 or something. So maybe that's an indication the coolant had indeed broken down.

Well it's a shame if the motor is shot because the truck has 135 original kilometers (84,000 miles) and drives real nice and straight. The interior is mint and the body is great with only a couple small surface rust spots. Plus the tranny shifts really good. I only paid $1,000 canadan for it ($820 US).

I always see vehicles for sale with rebuilt motors with low miles on the motor. Is it expensive to have a basic rebuild done on a motor?