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Engine 1991 Lx 5.0 Engine Rebuild Kit Inquiry

  • Thread starter Thread starter HotRodBlack
  • Start date Start date Apr 28, 2017

HotRodBlack

Active Member
Apr 24, 2017
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15
28
Apr 28, 2017
#1
  • Apr 28, 2017
  • #1
So, I'm not sure if anyone has seen my other post regarding my clutch issue, but between that problem and this next one, my poor car is down for the count.

After more or less diagnosing my clutch issue, i decided it was time for an oil change. That all went according to plan, except the Oil came out very thick. I suspect there was a quart of 'Motor honey' or that Lucas oil treatment in it.

So I balance my tires, fiddle with the headlights, put a couple bolts in the front bumper... Ok so the car is a bit of a basket case.

Added 4 quarts, start and idle for about 45 seconds, checked the level, added the 5th quart and started the motor up and let her idle.

Mechanical gauge reads 40 psi at a cold start. 10w 30 synthetic oil btw. I felt it was low, I believed it should be 60 psi on cold start. I stay above the 10 psi per 1000 rps the whole time. After 7 minutes oil pressure comes down to 11 psi at idle (600 rpm for me). I know that's not good.

And then I hear it... That infernal tap. Its not incredibly loud like a rod bearing gone missing... but it's in there. Deep, mechanical, and pronounced. No sir, that's not your garden variety lifter tick that you pray will go away on the ride home.

So I call the resident Old Guy in the shop. I'm 26, this car is as old as I am so its a bit before my time, professionally speaking. He gets his ear in there and plays with the throttle and makes the face. The Face that says it's broke.

He says it's a bearing, and possibly some piston slap. The motor is tired. This poor car...

Now that I've got you emotionally invested. The questions at hand are as follows:

What are your opinions on engine rebuild kits? Are there any you have used and would recommend?
I have found a very nice looking comprehensive kit from 'EngineTech' that comes with crank, rod, and cam bearings, a complete gasket set, pistons and rings, and all the various freeze plugs. Its under 300 dollars

After I get the motor out, I'm sure I'll be bugging you guys for tricks of the trade as I am unfamiliar with this engine. Alldata states to R/R a motor its 6.3 hours TOTAL with a complete unit, and 27.3 hours total to overhaul. I feel engine removal is the least of my worries.

Side bar: Im feeling like NOW is the time to either upgrade the Cylinder heads, with these GT40 heads I've heard so much about, or port/polishing the stock heads. I'm a bit leery about replacements because I don't want to deal with them if they don't just bolt on with my existing intake and headers. If it's 300 bucks for a set of heads, and the same price to service the ones I have, I feel like a port/polish is the way to go. That way I KNOW all the stuff will bolt back together.

I've Included two running videos of the engine for your viewing displeasure.

View: https://www.youtube.com/watch?v=ZKNuDI1Fcrk


View: https://www.youtube.com/watch?v=HMtkHLCbkAY


Pasted links. Still haven't gotten the hang of posting videos. Note: Yes I'm aware I am missing a header bolt on the right bank, hence that TSSICK sound lol

Feel free to chime in on the origin of the noise. I feel the end result is the same, requires a rebuild
 

General karthief

wonder how much it would cost to ship you a pair
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Apr 29, 2017
#2
  • Apr 29, 2017
  • #2
No comments needed, only thing I will say is about the heads, get better heads, gt40's at the least, aluminum if you can, your gonna get a wide variety of opinions on heads, just depends on future plans,
On another note, you need to 'close' your crankcase vent system, on your driver side valve cover it appears the oil fill cap is open to atmosphere, look at a stock 5.0, the oil fill tube is on the passenger side and has a tube running to the tb,
The oil fill cap on your valve cover is going to suck in junk that you don't want inside your new engine,
You could also look for an explorer/mountaineer with a 5.0 that will get you the better heads and possibly a good running engine that you can just swap out.
 

85ragtop

BTW, I like dudes.
10 Year Member
Nov 29, 1999
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Apr 29, 2017
#3
  • Apr 29, 2017
  • #3
I'll move this to 5.0 tech. The swap forum is for putting something other than a 5.0 in a fox.
 

HotRodBlack

Active Member
Apr 24, 2017
31
15
28
Apr 29, 2017
#4
  • Apr 29, 2017
  • #4
karthief said:
No comments needed, only thing I will say is about the heads, get better heads, gt40's at the least, aluminum if you can, your gonna get a wide variety of opinions on heads, just depends on future plans,
On another note, you need to 'close' your crankcase vent system, on your driver side valve cover it appears the oil fill cap is open to atmosphere, look at a stock 5.0, the oil fill tube is on the passenger side and has a tube running to the tb,
The oil fill cap on your valve cover is going to suck in junk that you don't want inside your new engine,
You could also look for an explorer/mountaineer with a 5.0 that will get you the better heads and possibly a good running engine that you can just swap out.
Click to expand...

Ok so I'm sold on the gt40 heads. I'll research and see if it's in my budget.

Problems I see with using an explorer motor:
1) I have to pull both motors... don't have the space.
2) what if I end up in the same boat with the donor motor after a few months?

I think I'll repair what's in there now. I want to get my hands on it and know what's what.

Ty for the crankcase vent tip. I knew that wasn't the correct spot for the fill cap. Why on earth would someone put that under the intake elbow on purpose. The other valve cover has a hole in it too but on the back side, so there's a little cap on it.
 
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