Howdy to all of you here,,Glad to be here too. I am a 71 year old that likes to work on cars and trks,,,mostly cause I gots to,,,
I recently got a 1991 Ranger Extended cab XTS with the 4.0 and 5 speed with 4X4. Trk only shows 86,565 and Cab is in very good shape (red). The PO told me it quit one day going to work and after tryin many times to re-start engine , he gave up and parked it for bout 6 months til he gifted trk to me. Yes. Trk was a No Crank-No Start so I pulled the starter and rebuilt it but still No Crank. So after several attempts I finally checked the big cable going to starter and the clamp at the battery had an ibnternal direct short,,! Never seen one like that,!! Trk would now crank but still No Start. Engine sounded like a NO compression problem so I pull spark plugs and you guessed it,,,Absolutely NO COMPRESSION at all,,,CHIT FIRE,,!!
OH NO,,,timing chain jump,,?? bent valves,,??
The tailpipe is very clean and does no show any signs of oil burning and spark plugs were all a nice whitish clean looking electrodes. At the very least, I could pull both heads to see what the extent of the damage to pistons or maybe just bent vaLVES ,,I could be so lucky,,OR,,,,OR,,,,,,
I have access to a 1996 Explorer with a 4.0 with only 65,455 miles that has a bad transfer case. Here is where I need some help.
Can somebody help me decode the VINs and/or the engine numbers on the tags in front of radiator to verify if the 4.0 in the Explorer will work in the Ranger without a lot of EEC issues,,??
Here are all the numbers.
Explorer: Built 10/95, VIN 1FMDU34X8TZA5227 Engine tag at Radiator: F6AE-9C485
Ranger Built 10/91 VIN 1FTCR15XONPA16941 Engine tag at Raditor F2AE-9C485
Can anybody help????

 

Welcome to the forum

They both have 8th VIN digit of X, this means they both have a 4.0l OHV engine, so the same engine

8th digit in a Ford VIN is the engine designation
Ranger VIN info here: https://therangerstation.com/tech_li...IN_Codes.shtml

4.0l OHV is a non-interference engine, so pistons and valve can never hit
It would be very hard to get no compression on all cylinders, even if timing chain broke, but yes if it has slipped
But this was never a problem on the OHV just on the 4.0l SOHC

The 4.0l OHV was a good reliable engine, 400k on the lower end was common

 

RonD,,,you have MADE MY DAY,,,yes you have,,!! I was hoping it was a non interference engine so the damage wshould be less severe,,I'm hoping,,!! I'm gonna pull the left side valve cover and take a look see at the rocker arms while cranking the engine and I bet money nuttin is moving there.
As I said in a previous post, the inside of tailpipe is nice and clean with just a himt of a gray powdery residue, which tells me the engine had not been burning any oil and spark plugs also tell same story. I'm thinking,I'm gonna have to remove radiator and disassemble the front of engine regardless of which way I decide to go with this based on the info you just gave me.
I'm way puzzled bout something tho,,,the 3 cylinders on left side did NOT registered any compression at all, and the middle cylinder on right side had none as well. I could not get to the other two spark plugs on right side to verify but figured if four cylinders have none ,,then those would not as well,,,??
"IF" the timing chain broke, then none of the valves would be opening and all would stay closed and cylinders should of been registering compression,,,right,,?? The only way the "NO COMPRESSION" could happen is if "ALL" the intake valves or "ALL" the exhausts are bent somehow,,,or "ALL" the pistons got holes in them,,?? I can't imagine the head gaskets leaking at "EVERY" cylinder to lose total compression,,,,?
Hoping you gots some more words of wisdom,,,I'm stumped,,,,,

 

No, the Cam would still hold some valves open if chain broke, but some would be closed as well, so engine would have a "lope" while cranking, as it hit closed valve cylinders

Timing chain skip or slip could produce 0psi compression as valves could be opening late or early not allowing any build up of compression
And that could probably only happen if woodruff key on the crank broke and allow gear to move out of time
That is fix-able

Head gasket or cracked head just lowers compression a bit, and yes not in all cylinders, so its not that

 

Hey RonD,,,I've been assigned other priorities for my time so have not had a chance to open up the front of the Ranger,,,hoping to get it done this weekend, tho,,,I am really keen to know what it is that happened. Need to see if I can get a manual coming. Thanks for all you help,,I do appreciate your input.