If your Timing became out of phase the low compression numbers CAN VERY WELL BE from a bent valve or valves now… Doing a “wet” compression test will reveal this…if your numbers dont go up much you have bent a valve or more than one valve… Thing is…you need to get the timing gear issue corrected BEFORE you can do the test that you need to perform.
Cyl heads for that engine rebuilt are actually QUITE CHEAP…so… Do what you gotta do
Blackbird
The valves in this engine do not even come close to hitting pistons. It is “free-wheeling”–they are of no concern in this case.
I have now removed the timing cover and the cam timing gear. That was a real bear. The timing gear was aluminum which I think means it is not the original(cloyes brand). It had some broken teeth but the dots still lined up which means it did not cause the timing to go out. The gear broke apart when removing it with a gear puller. This caused the tip of the puller to snap off in the end of the cam. Will I need a new cam? or can I get the gear on without that hole? I tried getting the tool tip out of the cam with no luck. Even if it would come out the threads are ruined in that hole.
I am now unable to pull the crank gear. It has no threaded holes and is to close to the engine to put a gear puller behind it. I think if I remove the main bearing cap I could get the puller back there but this involves dropping the oil pan which I would like to avoid. Does anyone have any magic tips for removing this SOB. Is removing that main bearing cap a bad idea?
Oh and before removing this stuff I reset the rotor to #1 at TDC and it started so it was definitely the timing that was off but how did it get off if the timing gears were not?
How did you set the rotor to TDC?
That means the rotor was pointing at the #1 post on the distr at TDC.
Or do you mean physically how did I do it? By loosening the bolt that holds the distr in place and rotating it.
If rotating the distributor into proper timing enabled you to start the engine how did the distributor get out of time?
If the cam timing marks are aligned then this brings you back to the compression numbers which you posted originally.
As I said, those numbers are garbage and should have been followed up on with a wet test; best done before tearing into the engine.
Have you pulled the distr? I would check the gear on that next.
Great minds, oldbodyman. That seems like a good possibility to me, also. Ford often used a pressed composite distributor gear that could break off or chip. I’m with you. Pull the distributor and inspect the drive gear.
I pulled the distributor and the teeth are good. The compression isn’t great but the numbers are the same as when I checked the compression a couple of years ago. I really haven’t put any miles on this truck in those 2 years since I only drive on short trips every few weeks. I was able to remove the cam gear with 2 pry bars and gentle tapping until it moved far enough to get the gear puller on it. My current problem is in trying to get the broken off gear puller tip in the cam I moved the cam back about 1/8 of an inch. After putting the cam gear back when it was almost touching the motor it was still about 1/8 inch away from where it was before. That’s how I can tell I shifted the cam. Did I ruin the rear thrust bearing? I’m ready to just put back together but have I f’d it up? What do you recommed?
“The timing gear was aluminum which I think means it is not the original(cloyes brand). It had some broken teeth but the dots still lined up which means it did not cause the timing to go out.”
Broken teeth means SOMETHING is/was seriously wrong. Was there a bolt and washer securing the gear to the cam? You can’t just slide a new gear on and forget about the broken off puller nose jammed in the threads
At the back side of the cam gallery is a freeze plug. If you push the cam towards the back, you will push out that plug, creating a massive oil leak…
There is a front thrust plate that holds the camshaft in place. There is no thrust toward the rear, the gears keep forward thrust on the camshaft. If there is no threaded hole in the center of the camshaft the gear is to be removed and installed on a press.
There was a threaded hole in the tip of the cam but it is now filled with the broken tip of the gear puller. In order to reinstall the cam gear I used the two thrust plate bolt holes, some long bolts and a stack of washers to press the gear back in place. Like is said before the gear came off it was flush with the cam now the cam is about 1/8 inch back from the gear face and this is with the gear almost touching the engine(AKA can’t go on any further.)
vintage.mitchell1.com/PClubData/chassis/ent81/V2D817023.pdf
This manual shows a plug(this must be the freeze plug mentioned by CAddyman) at the rear of the cam guess I pushed this out. Can anyone tell me if I’ve screwed it up or can I just pop that plug back in and then press the cam gear on the rest off the way?
You have most likely damaged the camshaft and one or more lifters. The lobes jammed against the lifters and held the cam when you pressed the gear on. You will need to pull the camshaft and inspect it and the lifters closely.
Don’t the lifters sit atop the cam lobes? How would they jam against the lobes? I hope this is not the case. When I pull the cam should I replace the lifters? What about the cam bearings? Can I pull the cam without removing the engine?
thanks
Dont just look at the gear on the distributor. Also check the pin that holds it on. On my Dad’s 85 300 6 cyl the pin broke and the gear moved. It was not till I tired to drive out the pin that I could tell it had moved.
Varying compression will not stop an engine from running. The timing chain might have slipped, but I think it would misfire if that were so.
If the camshaft is moved either forward or aft lobes will strike adjacent lifters.
You can remove the cam with removing the engine. You will have to pull the push rods and lifters. There is a panel on the side of the engine you take off to get at the lifters. If you take out the lifters you have make sure they go back were they came from. If you use a new cam you will need new lifters.