How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Doug Your Own Question
Doug
Doug, ASE Certified Technician
Category: Mitsubishi
Satisfied Customers: 6899
Experience:  Mitsubishi employed and Factory trained ASE certified technician
21364095
Type Your Mitsubishi Question Here...
Doug is online now
A new question is answered every 9 seconds

Mitsubishi: replacing cilynders heads in a montero 2005 3.8l

Customer Question

replacing cilynders heads in a montero 2005 3.8l limited?
Submitted: 1 year ago.
Category: Mitsubishi
Expert:  Doug replied 1 year ago.
Hi,
Have you checked your belt timing yet before getting involved in changing heads? If the leak down is good and there is no compression, I would be expecting the valve timing being wrong.
Customer: replied 1 year ago.
yes we did. Timing is right and we know because we did several times before changing heads. We'd shave it twice before so marks are all correct. we were thinking on timing but it looks alright and even if it was couple of teeth wrong it would have some kind of compression. this head mark 0 all 3 cylinders.
Anything else you may think of?? please
Expert:  Doug replied 1 year ago.
Hmm.... the problem I'm having is that if the leak down test shows 10% leakage, then that is about perfect... it is sealed up good. Which means you should have compression.
The 3.8 can't get the cams reversed, so that is out of the question... leaving really only belt timing that could cause no compression but good leak down.
No chance the dowels sheared off on the cams, allowing the cam gears to move?
Customer: replied 1 year ago.
no. Everything is tight...
are the cams the same right and left?
Expert:  Doug replied 1 year ago.
No they are different.... however the driver side cam is significantly longer than the passenger side cam, and as well has the threaded hole for the cam reluctor on the back. It would be near impossible to reverse them.
What are your compression numbers on the driver side?
Customer: replied 1 year ago.
driver side is about 120/130...
how about same side head? is there a different cams for the motor and year like for instance Dodge has?
Expert:  Doug replied 1 year ago.
Compression is pretty low on the driver side, but certainly not out of spec (typical is 220, minimum is 115 if I recall).
Having the wrong cams is certainly possible, 3.5 Montero cams would fit (As would the heads). Are these heads or cams potentially not the original ones from the engine?
Customer: replied 1 year ago.
yes I'd buy this heads on a reman place in california. They look exactly the same as the the original ones
Customer: replied 1 year ago.
Also want to ask about a granding noise. It sounds like starter noise only when it cranks but is sounds very bad. Chenged starer many times already and nothing. Cranking it even now with only one good head I can hear is still there. Any you can think on this or maybe somebody already asked about it??
Expert:  Doug replied 1 year ago.
Just to play it safe.... Lets take a look on both heads on the side, just above the center exhaust port. There is a casting there, what does each one say?
Regarding the starter... you probably have a wrong starter. It is almost impossible get aftermarket starters for these trucks because of the interchanges list all Monteros from 1997 on as the same starter used in the 97 Sport. Unfortunately there were 3 different Sport starters and 2-3 different Montero starters... and the one they push only fits 97 Sports. These get towed in from other shops all the time after they put an aftermarket starter on and it makes awful sounds and then they try selling a flywheel etc.
Just get the factory starter and you shouldn't have any more problems, provided no damage was done to the flywheel of course.
Customer: replied 1 year ago.
6g75s4 is the one in motor now.
6g7584 is the original one.
Expert:  Doug replied 1 year ago.
Thanks, ***** ***** there.
Looking at your photo I see you have the crank pulley on. When you aligned the belt, did you use the marks on the crank gear and the crank reluctor, or on the pulley itself?
Customer: replied 1 year ago.
All the crank gear has mark and the wheel.
Expert:  Doug replied 1 year ago.
Hmm. I was hoping perhaps you had used the pulley (as the mark does not line up the same). If you used the mark on the crank gear and the reluctor then you should be fine there too.
I don't really see anything here that adds up... even if you had the wrong (3.5) cams in there, it would still build compression.
Lets go back and double check the work, re-test compression and retest leak down. I would prefer testing leak down with the rocker shafts removed as well for the most accurate reading.

Related Mitsubishi Questions