New cylinder heads


jklolkik

5+ Year Member

Joined
Jan 18, 2019
Messages
30
Points
601
City
Tacoma,WA
Vehicle Year
1993
Engine
4.0 V6
Transmission
Manual
I am in the process of installing new heads. Thats on hold for now as 1 of the bolts holding the rocker arm assembly to the head broke.

I noticed 2 of my lifters have the center plastic cap broken off. They are for different cylinders and those pistons show signs of burning hot. Also the spark plugs are blistered.

Would this be a sign of bad lifters?

93 ford ranger rwd
 
Last edited:
You should probably start by telling us why you are installing new cylinder heads...
 
There was a pretty bad misfire and I was able to see a small crack between valves on the passenger side rear cylinder
 
Since when do rocker arms attach to the block? If you've got new heads how did the rocker shaft bolt break? If im reading this right it sounds like your engine over heated and cracked the head. Why did it over heat? I'm very confused. Some pictures may help.
 
When i get home i will take pictures.
That was a typo it was supposed to be to the cylinder head.
The bolt broke when torquing it down. Probably only got to 20 ft lbs then broke. Looks like it was an old crack where the bolt broke.
 
Here are the pictures of the heads and the cylinders in question
New cylinder heads

New cylinder heads

New cylinder heads

New cylinder heads
 
Gross... looks like it was running lean, overheated and burning oil all at the same time. Did you do any wet dry compression testing before taking the heads off? How do the cylinders and pistons look? How many miles are on this thing?
 
the cylinders look good the pistons on those 2 cylinders have heavy carbon. except for the very far side toward the fender it was clean bare metal on the piston. Did not do a compression test. Probably should have but with that side having a crack I didnt even think about the compression. miles no idea but for its age and its exchanged hands a couple times im guessing either close to 200k or over.

The coolant passages on the head gasket were heavily rusted. Going to flush it once i get it running again. Ideally I would take it out and fully tear it down and get it hot bathed, but dont have the time or space for that.
 
Would have been more logical to get a new engine. Goood luck.
 

Sponsored Ad

TRS Events & Gatherings

Featured Rangers

Want to see your truck here? Share your photos and details in the forum.

TRS Latest Video

Official TRS Merchandise

Follow TRS On Instagram

TRS Ranger Sponsors


Product Suggestions

Back
Top