4.0+M5R1 to 5.0+M5R2 (RWD) Swap Logistics

[97Sandbox]

Looks like I'm going to try to rescue a Mounty this weekend. Here's a bit more info from the seller:
"this thing just sat for almost a year I guess. And then when I started it it had this problem with the smoking. When I take the oil cap off it would clear up so I put a new PCV valve in it and a new vacuum purge solenoid in it but that didn't fix it"
"I don't know if it helps any with trying to figure it out but it happened from sitting. It ran fine when we parked it but it's set for 8 or 9 months and then when I decided to sell it I started it up and it ran fine for about four or five miles and then it started doing that. I looked it up on the internet said PC valve or purge solenoid valve and I replaced both of those and it did nothing so I gave up"

The fact that it clears up with the oil filter cap off is definitely interesting. Do you all think the symptoms point to crankcase ventilation issues? If all it takes to bring it back is cleaning that screen and spraying seafoam in the vacuum lines, it'd be quite a deal.

EDIT: Wanted to add the seller said CEL is not on. I'll bring my scanner to check for pending codes nonetheless.

 

[410Fortune]

Smoking from the exhaust? Is it coolant oil or fuel

 

[97Sandbox]

I could swear he said smoking in the engine bay rather than from exhaust, but re-reading my messages with him, I may have imagined that. If it is smoking from the exhaust, my understanding is:

• Blue smoke = oil = oil in combustion chamber = blowby from internal engine wear (seems unlikely for a 120k engine unless it was abused/neglected) and/or oil in crankcase ventilation system
• White smoke = coolant = coolant in combustion chamber = blown head gasket = run away!
• Black smoke = fuel = too much fuel = bad MAF or O2 sensor(s) -- would likely trigger CEL though, right?

In any case, does the "smoke clears when removing oil cap" point to anything in particular? I read some online yesterday but found a lot of junk without much substance except for a few folks saying probably PCV issue try replacing the valve (which is what the seller said he read and already tried).

My thought is that some blockage in the crankcase ventilation "circuit" is causing pressure to build where it shouldn't and oil is getting pushed/pulled from the crankcase. When the oil cap is removed, the pressure just vents to atmosphere and oil no longer gets forced where it shouldn't. Does that make sense?

I once had a bunch of oil get into my intake on my old SOHC Explorer and when I started poking around, I found the PCV valve had also popped out of its rubber boot at the back of the intake. In that case, I just sprayed out the PCV valve with solvent, cleaned the vacuum lines, breather tube, and throttle body and didn't have an issue again. If only this Mounty would be that easy of a fix...

 

[BigBlueBrick]

My thought is that some blockage in the crankcase ventilation "circuit" is causing pressure to build where it shouldn't and oil is getting pushed/pulled from the crankcase. When the oil cap is removed, the pressure just vents to atmosphere and oil no longer gets forced where it shouldn't. Does that make sense?

Makes sense to me

 

[410Fortune]

The pcv valve pops out if it’s grommet on the 5.0 all the time, I can actually hear it on a 302
When it happens. Once it does then the grommet gets weak and it happens more
Often the fix is some silicon to hold it firm

Once it’s out of its hole very easy to plug up that screen w gunk

Something to consider for sure!
A Stuck ring or leaky valve stems also
Common on higher mile 5.0
Does it puff blue smoke at startup from the tailpipe? This is a tale tale sign that oil making into combustion chamber

 

[97Sandbox]

Good to know about the pcv/boot situation. Looks like the boots are readily available if I need one.

I will look for blue smoke at startup too. If a ring is stuck from the vehicle sitting so long, would that be something a seafoam treatment could remedy, or are we talking about tearing into the engine?

 

[410Fortune]

I have un stuck rings using a concentration of marvel mystery oil in the crankcase before and again recently
Apparently the 4.0 ohv we got off embay had sat for a while before we purchased it had one stuck ring
I could actually feel when it loosened up the idle became baby butt smooth
It was using half quart of oil a week now it is not
Seafoam would accomplish the same thing
Now I’m going back to 5-30 Mobil one

 

[97Sandbox]

The Mounty was a no-go. I think the 302 would be saveable with enough seafoam and troubleshooting but my gut said the truck would not survive the trip home -- it was way rustier than even the seller seemed to realize and one leaf shackle was completely gone so the spring eye was just sitting on the frame. The interior was pretty rough too. The odometer really did say 121k, but the truck was worse in every way than my '97 was at 200k when I scrapped it. Just have to hold out for something better or at least closer to home.

 

[97Sandbox]

I've got a lead on another Mounty (this one's a '99) and this one looks less rusty and isn't nearly as far away. The price seems okay for a running/driving truck, but it's got 190k on the clock. I'm going to check it out and see if the engine seems well maintained as I figure a cared-for 190k is probably better than the neglected 120k of the last one I looked at. Not to mention, it's quite normal to run up a lot of "easy" miles here in rural Nebraska where just about everything is a 20-30 minute highway drive away.

This Mounty has plenty of issues (aka why it's cheap) but my primary concern is that it's losing coolant. I asked the seller if it's leaking coolant or burning coolant and she admitted she doesn't know. Can anyone comment on common leak spots to watch out for on a 302? If there's signs of burning coolant instead of leaking I will certainly not be purchasing haha!

 

[Turdle]

Heater core, and, timing cover can leak coolant.

Radiator may be cracked down low, shown by coolant pooling in lower plastic air dam duct under radiator.

Could be leaking at the small L shaped bypass hose
A clogged reservoir will also cause coolant loss.


I understand the rural challenge. I'm from straight north of you, town called Schuyler is where I was born. Actually lived in Rogers

 

[97Sandbox]

Heater core, and, timing cover can leak coolant.

Radiator may be cracked down low, shown by coolant pooling in lower plastic air dam duct under radiator.

Could be leaking at the small L shaped bypass hose
A clogged reservoir will also cause coolant loss.


I understand the rural challenge. I'm from straight north of you, town called Schuyler is where I was born. Actually lived in Rogers

Small world, my wife was born in Schuyler too!

I'll take a close look at all those areas. Hopefully it's leaking at some part that I'd be replacing anyway.

 

[CDW6212R]

Pull a spark plug or two, see if they are original(I've had two of my four with original plugs when I got them). What you want is most parts that should be replaced, all done at least once. The thing you don't want is all original engine and trans parts, suspension and fluids. Basic maintenance items are very valuable when done, and create problems when not done at that high mileage. You can live with some things, such as the suspension, but old fluids are a bad sign.

 

[97Sandbox]

Bought a donor! A pretty decent '99 Mounty which will have it's own thread here.