from head gasket to motor rebuild

[Skotty]

Buttoned up what was suppose to be a easy gasket job.Started the explorer and had what sounded like a dry lifter ticking.After a couple of seconds it quieted down.On the test drive everything ran like normal.Then all of a sudden I noticed the Oil pressure guage drop like a rock.I pulled over and It rose back up.Every time I gave it gas it did this little dance.I was about 3 miles from home so I decided to limp it home.Wrong!!! before I got it home the ticking sound returned.Thats when it happened.It sounded like a card stuck in a bicycle wheel then the motor jammed up.

So far I have the valve covers pulled off and the lifters and push rods seem to be fine.I am stumped and frustrated at the moment.Replacing all the gaskets and head bolts each time you tear it down is getting costly.

Any Ideas? I'm starting to think the timing chain went.

If I have to rebuild the whole thing any suggestions on getting more HP out of it?

By the way its a 92

Thanks for the info as this site has been a blessing

 

[TonkaRanger3.0]

is it a 4.0?

 

[Skotty]

yes 4.0

 

[TonkaRanger3.0]

OHV or SOHC?
because if its sohc the chain guides or tensioners are prolly shot
i have a 93 4.0 in a ranger and it does a little lifter tick now and then

 

[johnvosh]

OHV or SOHC?

the 91-94 only had the OHV engine, the SOHC didn't come out until 97.

 

[Roadrunner777]

So, jammed engine, cause unknown. Do you still have the pushrods and lifters out? If so, can you turn the crankshaft with a wrench?

 

[Skotty]

Sad thing is this is the first time it has been torn down this far.I can't see how something so horrific could happen just changing the head gasket unless it was just time to go.The engine has just turned over 160k.Oh well gives me a chance to change the rear main seal that has been leaking.

Guess I'll really find out when I get a chance to try and turn it over manually

 

[Skotty]

Lifters and pushrods are still intact and in their respectively place.With the little rattle and the end (sounded like something freewheeling) I am starting to believe it was the timing chain.

Saga continues.....

 

[Roadrunner777]

I wonder if there was something weird with the head gaskets that blocked an oil passage.

 

[Maniak]

Lifters and pushrods are still intact and in their respectively place.With the little rattle and the end (sounded like something freewheeling) I am starting to believe it was the timing chain.

Saga continues.....

I don't think I've ever read of someone breaking a timing chain on the 4.0 ohv motors.. Those motors pretty much run forever on the orig. timing chain. Anything is possible, but until you get things torn apart you not gong to really know.

~Mark

 

[arco777]

Oil pump went out?

 

[01sporty]

not sure about ohv motors but sohc motor head gaskets are designated left or right. but theycan be put on the wrong side and seemingly fit fine, except for the holes being covered up that go unnoticed until it is started and oil starved hope this is not the case. btw i work at jasper engines and have seen this problem happen and we end up getting a motor back for a 0 to 90 warranty

 

[Skotty]

theycan be put on the wrong side and seemingly fit fine, except for the holes being covered up that go unnoticed until it is started and oil starved hope this is not the case.

Will have to look at this.When the engine revved up the oil pressure gauge would bottom out.Oh well this gives me an excuse to pull the engine and overhaul it with a few goodies added in IE Cam,95m heads,new rocker arms and oversized valves

Read in someone's write up about a high pressure oil pump but am unable to find anyone that sells them anymore.....Is there any pro's or con's with them?

 

[jd4242]

M328 they still sell them!! Nothing but good things about it! If you only did heads the screen is probably clogged in the pump

 

[jd4242]

http://m.summitracing.com/parts/MEL-M328
Specs are wrong though, my post has the real tested spec
http://www.explorerforum.com/forums/showthread.php?t=247048

 

[Skotty]

Thinking of going with this kit Sealed power # MKP6261A-211 Just have to make sure the pistons are the right size.

Wonder what the difference is between the melling pump and the SP pump

 

[jd4242]

Both spec are in the thread i just posted.

 

[jd4242]

From my post #7
ok i just recalled milling and they assured me that this pump was made just for the 4.0 and that it will work and was made for a stock motor.they said that a stock oil pump runs(new motor and in spec with recommended oil) 25 idle and 54 at bypass and the new pump runs 34 at idle and 63 at bypass so it 9psi more and 20% increase in flow.they said this pump and numbers where made for a stock replacement and would work fine with stock bearings and clearances,so with that said im going to be putting this pump in next week when i tear my motor down again,ill post some updates and hopefully i dont run into any problems