Hi everybody,

I've got this '85 F-150, 302 (5.0) EFI. Just brought it home today. Fairly low mileage at 170,xxx KM (Canada). Truck sat for long periods of time.

The air filter and its housing have oil all over them. I opened up the oil cap and the PCV valve is not there at all, the grommet and elbow are though. Looking around for parts for this year, engine and fuel delivery type, the only PCV valves have two hose connections while the one on the truck has only one hose going from the oil cap to the air box (PCV filter missing also) and no others to be found.

Any suggestions? Seems to be very difficult to find information about this setup, tried the Haynes manual, trusty Google images, not much out there that gives enough specifics.

Thanks,

Mike

 

Apologies, I should have searched more thoroughly. I have found the answer about these aftermarket valves where the unnecessary port is plugged off unless required. Still very odd that the valve was not there at all. No issues driving down the road, however idles rough intermittently, as well as oil pressure light flashes here and there, mostly when stopped in drive or idling after longer trip.

 

Welcome to FTE.
Yes you did find the answer to the vale and the 2 ports.
I don't know where that PCV should be mounted on that motor if in the oil fill cap or in the valve cover?


I think you need to check the motor out a little bit to see what shape it is in.
First a compression test to see if that is why it idles ruff then maybe a tune up.


For the oil light might try a oil & filter change so you know you are starting with a good base.
If you still get the light you will need to use an after market gauge to see just what PSI you have at hot idle in drive.
If reading low, looks like time for new bearings but if you are getting oil in the air filter assy. it may need rings so a full rebuild would be needed.


I have gotten away with new main & rod bearings, old cam bearings, and new rings, old ones were stuck on the pistons and the motor ran great - used for drag racing.
Dave ----

 

The Hose in the oil cap is the PCV inlet or feed. The PCV valve is in the right hand valve cover at the back (near fire wall.) It's a bit tough to get at and see in the early EFI trucks.

If you have low oil pressure at idle it is symptomatic of worn bottom end bearings but as Dave said the only way to know for sure to sure is to hook a gauge up to the system to know for sure. The Oil in the air box is symptomatic of excessive blow by (worn rings/cylinders) But could be a bad PCV valve. You Will need to compression test it to know for sure.

Given that the you have oil in the air box and low oil pressure at idle at first glance it's looking like the engine is worn out and due for a rebuild.

Where in Canada are you located ?

 

The oil filler cap (on the driver's side when seated behind the wheel) should have a hose going from the cap to the (original air cleaner housing). The OEM oil fill cap served as a breather as well as feeding to the OEM air cleaner which had a Breather Element located
inside the OEM air cleaner housing. The PCV should be located in the passenger side valve cover. From left to right, this is how the Positive Crankcase Ventilation system was designed. When an aftermarket air cleaner is introduced, it bypasses the OEM system causing all sorts of grief, from the issues that you are experiencing, to hard starts when cold as well as hot. It took me 6 months to track down an OEM air cleaner housing to return Blue Ox to proper operating condition as built by Ford and it was the best effort I ever spent.

 

His is EFI not carbed. Little different situation.

 

There are TWO possible locations for the smog valve:

Right valve cover: The smog valve fits into a rubber grommet. Smog hose routes from smog valve to nipple on rear of air cleaner.

Left valve cover: The oil cap fits into the valve cover, rubber grommet fits into oil cap, plastic elbow fits into grommet. Hose routes from elbow to nipple on front of air cleaner.
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Right valve cover: Rubber grommet fits into valve cover, plastic elbow fits into grommet. Smog hose routes from plastic elbow to nipple on air cleaner.

Left valve cover: Oil cap fits into valve cover, rubber grommet fits into oil cap. Smog valve fits into rubber grommet. Smog hose routes from valve to nipple on front of carb.

 

I've never seen the PCV in oil cap on an early EFI, here all have been in the right rear valve cover. There was also TSB in 93 for the rear mounted PCV Dumping to much crap in to Cyl 7 and 8 in the original location and it was rerouted to the vacuum tree that the brake booster hooks too.

 

I've never seen the valve in the oil cap either, but the 1980/89 truck parts catalog shows it this way for 1980/85 302/351W

I listed the smog valve in right valve cover, elbow in oil cap on left valve cover, because every 1968/80's truck V8 (gas) I've seen used a similar setup.

 

Ya suspect they were referring to Carb engines in the book in regards to the PCV in the Oil cap. I have never seen a carbed 85 F150 5.0L in person I know they existed but must have been a pretty uncommon configuration.

 

Thanks so much for all your answers. I had some time to take a closer look today and the PCV valve is indeed closer to the rear of the passenger side valve cover. It's a Motorcraft, looks fairly new and rattles nicely. I was confused when looking at some Google results which showed it in the breather cap, where it's located on carbed engines.

I'm located in the cold north near Alaska.

Matthewq4b, where did you get that diagram? I have the factory manual and couldn't even find it in there.

I also found that the crankcase breather filter was missing from the air box which I replaced for a few bucks. Don't have a compression tester at the moment but hopefully it's not a compression issue at such a low mileage. Again, it does drive very smoothly, but the oil pressure light flashes on and off at idle and not all the time. For example it hasn't done it while stopped at a stop light.

I'll check the oil condition when I change it next week sometime but it is dirty at first glance. The guy I got it from said it burns a bit of oil. About a quart every 2000km or so back when he was using it regularly.

 

Near Alaska...would that be in the Yukon or Northern B.C ? if the truck spent it's whole life in those northern latitudes there is a very real possibility the engine is just worn out. Cold weather starts eat engines up real quick. And a Quart/Liter every couple thousand km's is a good sign that the rings/ valve guides have a good amount of wear on them.

The Pic I believe is from a shop manual (chiton/haynes) or the parts catalogue it is one I have had on my comp for quite awhile, as that question pops up more often than you think

 

Yep, it's the Yukon. The truck originally came from Edmonton and was driven up here in 2000. It's a second vehicle for me, basically just a camping / off-road kind of deal so I won't be rebuilding the engine or anything like that, will catch up on the neglected maintenance though. No big deal to dump some oil in there now and then. I wouldn't be too surprised though if the rings are done, the guy said it sat for about 8 years after which he had to get a whole bunch of seals done (didn't remember which ones). He did keep it plugged in through for the winters where he used it regularly.

The rough idle feels more like vacuum leak which I haven't had time to look for yet. I did remove the throttle body and ABV both of which the gaskets crumbled right off.

 

Ah so it is from my part of the world then.

Is the ABV functioning properly ? They can get sticky and screw with the idle would not hurt to give it a rinse out with some carb cleaner if you did not do that when it was out.
And chase some of the vacuum lines they are more than likely cracked and failed in a few places.

I love the Yukon, the winters not so much... I always look forward to the flights on Air North by far the best North American Airline. I have spent a fair bit of time up there in the Yukon mostly in Haines Junction and the Kluane's, so I'm familiar with the conditions it has been exposed to. You will get it all sorted out eventually.

 

Small world. I came up here from Vancouver and haven't looked back. Winters are just something you get used to, no big deal.

The throttle was carboned up really bad, so I scrubbed that out with throttle cleaner. Soaked the ABV as well. Might give it a tap next time I start it up, if it runs rough. They're both still off since I have to wait for the gaskets. The upper intake is caked too, might run some sea foam through there. I haven't checked every vacuum line but the ones I did all have been perfect.

I've been driving through the winters up here for a while, most engines that die seem to be from either not being plugged in, starting it and driving off right away every time, lack of maintenance, or a combo of all those.