Japp! Then I have a Hall sensor... so can I just put it back and look even more closely if it spins when engine cranks or do I have to find TDC only fore doing that?

 

You can drop it in and see if cranking engine spins it, no timing needed.
You should tighten the bolt or the whole thing will spin

 

Great! To be continued :)!

 

Hello again! I put it back and crankt the engine but the synchronizer didn't move at al... so I guess I'm one of the rare ones that have a broken chain on this engines? Dead tired of this **** now :(!

 

And if the chain is of was there enough room for the valves to go back up safely without geting hit by a piston? I've heard that some engines have enough room no mater what.

 

4.0l OHV is a non-interference engine, that means the valves and pistons do NOT share space in the cylinder, so valve wide open and piston at TDC won't touch.

An Interference engine does have valves and pistons that share space in cylinder, so valves and pistons can touch, usually compression ratio above 9.5:1 will be interference
4.0l OHV is 9.0:1
4.0l SOHC is 9.7:1 and is an interference engine, contrary to some reports

No cam movement means no compression and no running engine, I thought engine ran but was throwing 340 code?

 

Ahh!!! You are far more better than any Heynes or Clymer workshopmanual Ron! I'm really impressed! Well the engine don't run but the starter cranks it around and there is spark but it won't fire. And the synchro doesn't move and the code read P0340

 

Well then cam is probably not moving :)

But it should "sound funny" when cranking, most cylinders will have no compression because a valve is open and others will have too much because both valves are closed, so a "lope" when cranking.

Broken chain could happen but more likely woodruff key on crank was sheared off, so crank turns but crank timing gear doesn't.
Still have to pull off the front timing chain cover so no less work one way or the other

Should be fairly straight forward
I don't think you have to remove the oil pan but will need to loosen it and drop the front down a bit

There is not alot of info on doing this repair out on the net because it simply never happens on the 4.0l OHV, so you have a bit of a unicorn problem.
I would pull out #1 and #2 spark plugs just to confirm you have no compression
Or pull off 1 valve cover to confirm valves are not working

 

Well I'm not giving up yet! The truck is in really great condition so this has to be done before I give it up. I'll try to figure out the procedure and se what's wrong. Woodruff key don't sound that expensive but a lot of work... but I will do a compression test and also look at the valves. I need to find the TDC anyway... you never stop learning :)! I wish you a merry Christmas and to be continued.
Mattias

 

Merry Christmas

 

Hi Ron!
tgought I would update the work with my ranger. The problem was the tap on the backside of the cam shaft sprocket had broken of. I think it's because of the center torx bolt that was very loose an actually broke of when I turned it by hand. So new parts is on the way from the states to Sweden now :)!

To be continued

 

Thanks for the update :)

 

Hi Ron!

Now when i finally received my new parts to start rebuild the cam shaft I have some questions about the TDC. I've seen a lot of people on YouTube using a screwdriver, a baloon, a vacuum Gauge etc... but I was thinking that now when I have the cam shaft cover off i should be able to se it without using the methods above? I can't see any marks on the crank or cam sprockets but I read in Heynes that the cam and crank should line up using the "pockets" for the woodruff key. But should they line up against each other, away from each other, or up or down? Could it really be that simple? How do I know if it's on compression stroke when it's lined up or it can't be wrong when it's lined up? I'm getting closer now but don't want to put it together without being 100%

kind regards Mattias