91 2.9 compression problems - Ranger-Forums - The Ultimate Ford Ranger Resource
Ford Ranger Forum - Forums for Ford Ranger enthusiast!

Go Back   Ranger-Forums - The Ultimate Ford Ranger Resource Arrow Ranger-Forums Technical Engine Forum Arrow 2.9L & 3.0L V6 Tech

2.9L & 3.0L V6 Tech General discussion of 2.9L and 3.0L V6 Ford Ranger engines.

LinkBack Thread Tools Search this Thread
Old 11-21-2015
Thread Starter

I am: Bobby
Join Date: Nov 2015
Location: Dayton nevada
Vehicle: 91 Ranger
Drive Type: 4x4
Engine: 2.9
Posts: 1
Total Props: 0
91 2.9 compression problems

New to fords just got a 91 ranger with a 2.9 and drivers side cylinders have 140 across and passengers side starting at number 2 has 0, 30, 90. I've been told numerous things from head gasket to collapsed lifter to a bad valve train I wanna see what others have to say about it that actually have a ranger. Thanks-Bob
Reply With Quote
+ 0 -
Old 11-21-2015
iTrader: (1)
I am: Ron Dean
Join Date: Jan 2014
Location: Vancouver, BC
Vehicle: 1994 Ford Ranger
Drive Type: 4x4
Engine: 4.0
Posts: 4,756
Total Props: 88
2.9l shows factory 9.0:1 compression ratio

This would mean you would expect 160psi if testing between sea level and 2,000ft
I use 18 times ratio to get expected PSI, 18 x 9 = 162, some use 18.3 but unless engine is newer I find 18 is usually closer to reality, lol

But compression tests are not about high numbers since that varies with gauge, battery(crank speed) and testing methods.

So 140psi on drivers side would be OK

The passenger side reads like a problem, bad head gasket won't get down to 0psi, badly burnt exhaust valve or hole in the piston would, mis-adjusted rocker could be holding open a valve as well.
If you have an air compressor you can hook air hose to 0psi cylinder and listen at tail pipe or throttle plate to see where air is going.
Or dipstick tube(piston hole)

But in any case that head, both heads, will need to come off
Reply With Quote
+ 0 -

Similar Threads
Thread Thread Starter Forum Replies Last Post
Compression M1keyV 2.3L & 2.5L I4 Tech 6 07-24-2009 12:41 PM
For Sale: BOSS guitar pedals, engine compression kit (GA) black_edge4628 Engine & Drivetrain 0 06-22-2009 01:33 PM
engine compression low??? chass1971 2.9L & 3.0L V6 Tech 6 01-02-2008 01:32 PM
lost compression? JRanger 2.9L & 3.0L V6 Tech 2 02-24-2007 11:21 AM
Compression and Vaccuum loopholes little4040 2.3L & 2.5L I4 Tech 9 04-10-2006 08:08 PM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -6. The time now is 03:16 PM.