I very recently bought a 351w-equipped '88 F-250. This is now my second Ford truck (Careful, you buy one, you want them all..) The truck has a lot of miles on it. The odometer says 58k, but we all know what that means.

Anyway, my question is this. I want to see what kind of shape the engine is in. I know a compression test should be the first thing I do, but I've seen people talk about leakdown tests and other things. What exactly is a leakdown test, and what does it tell me about the engine? Also, how would I test the oil pressure? I know there's a gauge in the dash, but it doesn't tell me much.

Another question - I will be replacing what I hope is a blown head gasket. Should I replace the gasket on both heads? Should I also get the heads magnafluxed and milled if they need it?

This is going to be a project, so I will have *lots* of questions in the future.. thanks everyone!

 

 

Anybody?

 

[updated:LAST EDITED ON 19-Aug-02 AT 11:08 AM (EST)]I belive a leakdown test is when you hook an air compressor into one of your sparkplug holes and listen for an air leak through one of your valves, tells you if they are closed or such.

When you pull your heads, do both gaskets at once, it will save alot of hassle that you won't have to worry about later.



Get one of those gauges from autozone that shows your oil pressure, hook it to the sender on your engine already and see what it does. (it may come with its own sender to put into the engine, not sure.)

 

The compression test and the oil pressure test will give you a good idea of how good of a condition your truck engine is in. You might also want to do a fuel pressure test, thats simple too. If you need directions I can help you. I just don't have my haynes book or ford book available this minute. And you will want to replace both of those gaskets.


Primary rig is Green Thunder:
95' F-150 XLT 4x4, 302, 5 spd, MSD 6A, Flowmaster American Thunder Exhaust, Sunroof, Clear corners w/ Diamond headlights, CD player with 2 10" subs and some 32" BFG Muds .

Check out my Gallery for a look-see.

Then theres:
99' Mustang GT 4.6L
88' F-250 Heavyduty 4x4 351/c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 with a
3 spd column shifter. Weighs around 7,000lbs w. 65mph top speed, who wants to race me!

 

I've done a fuel pressure test on my other truck, so I'm pretty familiar with that.

I've never done the compression or oil pressure tests, but hopefully the gauge will come with decent directions so I won't have to embarrass myself too badly here.

Hopefully, I'll pick the gauges up this weekend. If I really get stuck, I'll be back.

Thanks everyone!

 

Save yourself future headaches. Buy a used, rebuildable 351W for $100-150 and rebuild it. A fairly stock rebuild would only run a couple hundred bucks. Even if you needed to bore it and get a crank kit, you are still looking at under $1000, and you will have a durable, dependable motor.