1996 Explorer 5.0 cam synchronizer stuck (engine gurus help!)

[fishinman78]

This is not really Bronco related, but I am hoping since it is a 5.0 it could be slightly related so I can get some help from the engine guys. I am really in a bind on this.

My daughters 1996 Explorer developed a squealing noise at idle. I though it might be a pulley but it wasn't. It turned out to be the cam synchro. I guess this is a common problem for the busing to go bad and then squeal. I thought no big deal I have worked on a few of these and I have an Explorer 5.0 motor in my 1976 (Look, it is Bronco related now!) so I thought i would just swap it out. Now here comes the problem. It is stuck... and I mean STUCK!!

The housing rotated freely, but I couldn't get the thing to come out. I put the alignment tool on it thinking I could grab a hold of it and get it to rotate up and out like a distributor, but it bent the little half round piece inside the synchronizer. I pulled and pushed and tapped but I couldn't get it out. After about three hours of frustration, I drilled the top of the shaft off and pulled the housing off thinking I could get a hold of it with vice grips or something to pull it out...wrong.

After screwing with it for another couple hours, I thought to myself, the only way I am going to get his thing free is to pull the timing cover and see what is going on. So that is what I did.

I pulled the cover and was able to get the cam out maybe a 1/16 of an inch or a little more. I can see that the gear on the synchro is not binding on the cam. It is just stuck, on what I am thinking is maybe the oil pump shaft. I got a long punch and tried to hit it up from underneath the collar on the shaft but that didn't work.

So don't laugh at this because I really was getting pissed at the stupid thing. I finally hooked my cherry picker with vice grips to it and gave it a tug while I taped a rotated and that wouldn't even budge it...

The car has about 130k on it and by no means is a piece of junk, but I am not interested in putting an engine or anything in it. I would rather just part it out if it came down to it.. its a $1500-$2000 car and I just don't have the time.

Any ideas or suggestions would be appreciated. This isn't my first rodeo, and I really feel like I have given it everything I can think of.

I am just hoping maybe someone else has a brilliant idea.

 

[EFI Guy]

Wow! Can't say I've ever seen that before. If I had to guess... When the bushing wore out it allowed the bottom of the shaft to wobble and rub against the block. It probably mushroomed the end a little bit so now the shaft won't come back through the block. I think I would try a slide hammer and try to keep it as straight as possible.

 

[fishinman78]

Wow! Can't say I've ever seen that before. If I had to guess... When the bushing wore out it allowed the bottom of the shaft to wobble and rub against the block. It probably mushroomed the end a little bit so now the shaft won't come back through the block. I think I would try a slide hammer and try to keep it as straight as possible.

How would I attach the slide hammer to the shaft?

 

[Broncobowsher]

Can you drop the pan, pull the pump, and punch it up from the bottom?

 

[jagbucket]

looks like a roll pin on the bushing/spacer try punching that out

 

[fishinman78]

Can you drop the pan, pull the pump, and punch it up from the bottom?

I am not sure I can do that without pulling some of the front axle/suspension components

 

[fishinman78]

looks like a roll pin on the bushing/spacer try punching that out

That's not actually where the issues is. There is alot of room around the spacer to get it out

It seems to be stuck below the gear in the synchronizer

I originally thought the gear was bad before I pulled the timing chain cover but now my thought is the oil pump shaft almost like it twisted the shaft or something or like EFI guy said it's wallowed out the block below the gear

 

[DirtDonk]

Sorry to hear you're having to go to such lengths for such a small part fishinman!
But I'm having a hard time coinciding what I know with the pictures.

In pic #2 you can see that the housing for the sensor is still in the block, but pic #3 from up top shows the "cover" (if that's what it is?) has been removed and only the shaft and outer housing remain. I did not know they came apart frankly, but you can clearly see (I think) the thin aluminum cylinder layer still in the top of the block.
When you said the housing spins but won't come out, did you mean the top part that is now removed? Or the part remaining in the block? Does the part remaining in the block spin easily by hand, or perhaps with a little persuasion still? Or could it be what is resisting?

It's way more common nowadays to find the aluminum housings of distributors (and therefor probably cam sensors as well) to be literally frozen solid in the engine block. Aluminum mixed with cast-iron, and all that brings...
Just wondering if that's what you're actually dealing with, and not a shaft issue.

But if that piece still spins and only the shaft and gear won't come up, have you seen if you get any extra movement by turning the cam by hand at the same time? I see the bolt in the center, so presumably you've been messing with the cam a bit, so just checking to make sure we're on the same chapter.

Good luck. Only other thing I can think of is perhaps applying some heat. Unfortunately both the sensor shaft and the pump drive shaft are steel, so other than their diameter and thickness differences, could expand and contract at near the same rate.
But it might be worth a shot.

And one last question. The gear looks clean, but awful dry in that first pic. Did you by any chance clean it all up with carb or brake cleaner before it was taken? If so, good. Otherwise things look pretty devoid of oil in that area.

Good luck again.

Paul

 

[rjrobin2002]

I am wondering if the aluminum housing is seized to the block myself. Heat the area of the block it slips in and see if the expansion releases it.

Another option is to cut the lower section in half you can access with a angle grinder and use a punch from below to knock it up.

Or weld something big to it a slide hammer can attach and go after it.

 

[Broncobowsher]

I'm betting it is the aluminum seized in the iron block. That was fairly common with distributors when someone would not adjust it for a long time. there were tricks like using an oil filter wrench on the distributor. And sometimes you could not adjust it and I've heard of people trying so hard they broke the top off the distributor.

Looking at the pictures a little more, put a slap hammer on the shaft and try and knock it up that way.

 

[jamesroney]

OK, you got me with "cam synchronizer." I was thinking cam Phaser, and then thought that you somehow managed to get variable valve timing in a 5.0 roller engine, and that got me interested.

Then I was disappointed to learn that the cam synchro is not a synchronizer at all...it's just a fancy name for an oil pump drive and camshaft proximity sensor.

So that was worth investigation. I went into the garage and pulled the roller cam out of my 5.0 shortblock. With the oil pump drive in place, the camshaft will not come out of the block. It will hang on the first cam lobe. I got it to come out about 3/8 of an inch, but that's it. The picture is shown below. So you can stop trying to pull the cam. It's not coming out.

It appears that your cam synchronizer is stuck in the block. You need to extract it. As recommended above...one way is to remove the oil pump, and drive it out from the bottom. Otherwise, you might want to weld a nut to that shaft, and put a puller on it. Then extract the shaft. You might end up shearing off the roll pins, but since the timing cover is off...you can catch the gear. Once the shaft is extracted, you can thread the aluminum housing bore with a big tap, install a long bolt, and pull the stuck housing out. You should be able to get enough force on it. Hopefully it will pull with the shaft.

Did you say that you could rotate the aluminum housing in the cast iron block freely? That seems strange.

Best of luck.

 

[lagbolt]

Fisherman78 did u ever get this taken care of ? I have the same problem going on with my 97 explorer motor in my 71 bronco. I got the cam synchronizer out but when I used a slap hammer to remove it the cam welded itself to the block and has a crack now where the bottom of the cam rides on the block, right where the oil pump shaft rides. Just curious if yours happen to do the same thing and if so did you just throw a new one back in with a crack on the block side?

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