Pirate Tom

Hey guys, I'm working on my mom's truck, which has sat for a couple of years, and was barely running. I've got it going. Pulls good going down the road at speed, though a little weak on low end torque when moving around the yard, (Lots of ruts/hills, I've got to give it a bit more gas than I'd like to get over them.)

Basic info: 1987 F-150, 302 V8 with 4 speed manual trans.

The main concern I have right now is that I feel like the engine is running hot. I have no working temp gauge at the moment though, so I can't tell.
I plan on getting a infrared heat gauge from a buddy this weekend to measure at least surface temp on the engine, but don't have that yet.

But, It just seems to radiate a lot of heat after running for fairly short amounts of time, and if I pull the oil dipstick out, it smokes. and you can see the fumes coming out of the tube. The oil pressure gauge *Seems* to work (Varies slightly with RPM), but always reads *just* above the red line.
The top radiator hose is getting fluid in it, so I'm assuming the thermostat is working, but I will be pulling that out to test shortly.

I had done an oil change on it merely a month ago, and have been checking fluids every time I crank it up out of paranoia (It sat for about 10 years, so who knows what could be wrong with it.) Last time I took it for a 20 minute drive, I noticed fumes from under the hood, and could "smell" the heat (Leaves and oil and assorted crud in the engine bay getting hot) I took it slow home, and when I got back, the oil was low.

Cardboard placed under the truck shows no sign of leaks, Spark plugs look good and the exhaust seems clear, so it doesn't seem to be burning oil.

My question is, does it seem likely that something is up with the oil pump/pump filter, and maybe it's not flowing enough oil pressure to keep things cool? It hasn't blown up yet, so I think I've been lucky enough that it's kept things just lubricated enough to survive, but worried that might not be the case for long. Maybe it's actually smoking off the oil inside the engine and it's been coming out of the dipstick tube or elsewhere? (There is a black coating baked on the dipstick above where the liquid oil sits.)

Do you guys think I'm going down the right track, and need to check/replace the oil pump, or am I chasing the wrong thing here and missing something?


Replace parts so far:
TFI Module, Distributor, Ignition Coil, Buncha brake parts, EGR Valve, Fuel Gauge sending units, buncha vacuum lines. Rubber suspension components that were dry rotted.

88xlt

I wouldn't jump to conclusions about replacing the oil pump. The oil pressure gauge in there is probably just an idiot gauge that moves to some point with adequate oil pressure and will go clear to the left when the oil pressure drops below, they say about 7 PSI.

There should be a red ENGINE light in the lower left of your dash that will light up when the oil pressure drops too low.

One thing I would replace is the PCV valve, it may help with the smoking out of the dipstick tube. Use only a genuine Ford replacement. It would be nice to get your temperature gauge working, I would check the sending unit or the wire coming from it.

Pirate Tom

Thanks for the feed back. I hadn't done the PCV yet. I'll check into that.

I hadn't mentioned it, but I unhooked the sending wire and measured resistance on the temp sensor, and got a nice linear reduction in resistance as the motor warmed up, so that seems okay, and there was power on the lead for it, that didn't quite match what the manual seems to suggest it should be.
Manual says it's likely a bad instrument gauge voltage regulator, but I can't find mention of that anywhere else, so not sure where it's located. All the other gauges work though.

So I'm not sure that it's the power to it. I think that particular gauge may be bad. LMC carries a N.O.S. one, but for $70. And I'm not looking forward to tearing out the dash to replace it.

The needle on the oil gauge is right now, when running and idling, perfectly lined up with the white line demarcating the bottom of the oil pressure range. If you rev it, it goes about half a needles width up, and that's it.

Lazarus-F150

It sounds like you have two minor symptoms of a blown head gasket. What's the color of your engine oil? Does it have any milky appearance? Try these easy tests: http://troubleshootmyvehicle.com/for...-head-gasket-1

Pirate Tom

I take the two symptoms are the over heat and oil pressure gauge? Right now the engine oil looks pristine, but I did do an oil change, and add some fresh oil not very long ago, and it hasn't been running too much since. So may not be highly contaminated yet. As I recall when I did the change, the oil was black, but didn't look like coolant contamination. (had a Saturn once with a classic blown head gasket, so I do know what it'll look like when really bad at least.) I haven't noticed any signs of anti-freeze in the exhaust yet either, but I'll definitely do the tests linked in the post. I don't have a compression tester, but I can walk out and check the radiator right now. Thanks.

Pirate Tom

So, found not what I expected. With the engine off, and cold (Not run since yesterday), I removed the radiator cap, and somewhere between 1/2 to 3/4 of a cup of antifreeze shoots out. Then I go to crank the engine, and the antifreeze stays in the radiator fine. Shut it down. Recap the radiator, restart and run again for about one minute. Shut it down, go back and remove the cap and it shoots out another 1/2 cup. So obviously the system is building up pressure in the coolant system and holding it pretty well even over time. Not something I've seen quite like that before though.

Lazarus-F150

I've got that going on at the moment too and I'm not sure what to make of it either...

Lazarus-F150

Also, I would agree with Pirate Tom that the PCV may also be your problem since you would be building pressure in the oil system if it's failed that may lead to the fumes that you are seeing. Thankfully, it's easy to test. Pull it out and shake it. If it rattles then it's in good shape. If not, time for a new one. I've heard a lot about how this is one of those things that you want to buy the Motorcraft part for (I recently bought one from Rockauto). Just be sure to get the one that's matched to your configuration. For some reason that I have yet to understand they are even classified by 2WD and 4WD...

sdmartin65

Sounds like a blown head gasket at an exhaust port, not as common. This will push exhaust into cooling system and cause overheating while driving. A lot of time the vehicle can run at idle this way forever.

SaltEater

Def do a compression test. I have a 1990 that does the same thing; fumes out the dipstick, dies under load.

Also if you do have fumes out the dipstick, then breather tube (oil fill neck to airbox) may have fouled the air intake. So fun times cleaning that out.

Hopefully its just the pcv, way cheaper than dealing with the alternative.