Need urgent advice timing an 84 351W... There is something strange going on

[MaineBroncoBeast]

Hello,

This summer I clean up the engine bay and pulled the distributor. I did mark the position and photographed it so I could drop it back in. When I was ready to start the engine again, I dropped the distributor back in same position and couldn't get it to start and ruined a starter. I suspected the timing was off so I did the normal routine of removing distributor, turning the crank until I had TDC on spark plug #1 compression ******* marked the distributor cap at the 1 mark and transferred the mark to the base. Then I dropped the distributor back in and seated it so that rotor was pointed at the 1 mark. I disconnected the distributor advance vacuum hose and plugged it.

I've done this many times but this time something is different... I have the harmonic balancer marked at 10 btdc. When I turned the crank to get the TDC spark plug 1 compression ******* the mark on the harmonic balancer was about 1.5 inches ccw to the timing marker.

I turned the crank (1.5" cw) to line up the 10 btdc on HB to the timing marker and dropped in the distributor to line up with mark on distributor pointing to 1 on cap. I got it to start but it was a hard start. I turned the distributor to get best idle and checked with the timing light... it was 1.5" ccw to the timing marker flashing steady. When I turned it back to line up with timing marker it was running rough.

I repeated the process again except this time when I reached TDC compression ****** on plug 1 (still 1.5" ccw), Instead of turning the crank to line up with timing marker, I just dropped the distributor back in, lined up the rotor and started the engine. The timing light still showed best idle at 1.5"ccw from the timing marker. If I turned the distributor to line up with the timing marker the engine ran rough again.

I took it for a short drive on my property and it seemed to run okay...

Every other time I've done the timing it has always timed to the marker at 10 btdc. Have I done something wrong? Any advice or wisdom from the experts will be much appreciated.

 

[Tiha]

So TDC on the harmonic balancer, is it lined up with the mark when 1 cylinder is at tdc?

Harmonic balancers can slip. Timing chains can jump.

 

[MaineBroncoBeast]

I have the harmonic balancer marked at 10 btdc. When I turn the crank to get plug#1 to TDC compression ******* the mark for 10 btdc is 1.5" before timing marker... normally it should 10 btdc at timing marker.

 

[Tiha]

I think you are going to have to mark your harmonic balancer again. 1.5" seems like a long way from TDC I thought it was more like an inch or less.

But maybe someone else can measure.

Either way, balancer marks, cylinder orientation has nothing to do with distributor placement.

If it was me I would get some timing tape and remark the balancer.

 

[MaineBroncoBeast]

I think you are going to have to mark your harmonic balancer again. 1.5" seems like a long way from TDC I thought it was more like an inch or less.

But maybe someone else can measure.

Either way, balancer marks, cylinder orientation has nothing to do with distributor placement.

If it was me I would get some timing tape and remark the balancer.

The balancer has all the timing marks clearly visible so no need to remark or retape. When setting initial timing, there is a procedure to follow and marking the balancer and setting TDC on plug 1 are part of the process or else why bother at all.

I'm asking why does the 10 btdc mark I've highlighted with white out on the balancer be about 1.5" before the timing pointer when spark plug #1 is at TDC of compression ****** when it should've lined up with the timing pointer?

 

[MaineBroncoBeast]

I will be checking the harmonic balancer for slipping tomorrow morning.

 

[Ric330]

Shouldn't Zero be in line with the timing pointer when #1 is at TDC? Then while it's running you adjust it to the 10degree mark you made?

 

[miesk5]

Yo,
Headache here, so some iinfo from Ford:
Refer to the following illustrations for cylinder numbering of block and distributor for firing orders and timing mark locations.

Base ignition timing is preset at 10° ± 2° BTDC.

 

[MaineBroncoBeast]

Thanks for the info but I have all of this and that's how it is wired. The timing marks are clearly visible on the HB. Today I set it to 0 TDC for initial timing at timing pointer and set the distributor for rotor pointing to #1 on cap. Was a rough start and once again the engine ran best with the timing light showing 10 btdc in the middle portion of the timing pointer (the half circle notch), about an inch from where it should be. When I turn the dist cw to get the 10 btdc mark on HB to flash at the timing pointer, the engine runs rough again. The vacuum advance at bottom of distributor was turned as far left as it could go when engine ran the best which isn't normal.

I looked to see if anything was visibly wrong with the HB but I couldn't tell if it had slipped or not. I didn't notice any alignment marks for the 2 parts of the HB to indicate if it had slipped. I have the harmonic balancer removal/install kit so I can get a new HB tomorrow, my parts store has one in stock.

How could I tell if it's the timing chain? Nothing about the engine has indicated it has slipped or failed.

I do have several new EEC-IV computers, I'll replace the one on it now and see if that helps.

 

[MaineBroncoBeast]

I'm going to drop the distributor a notch ahead or behind to see if that changes anything... all done for today. Pizza time

 

[miesk5]

Yo Maine,
by Chilton
●

 

[johnnyreb]

Yo Maine,View attachment 28662View attachment 28663
by Chilton
●

 

[johnnyreb]

Something to remember is parts wear and you can not always go buy the book Miensk told you right. Now when I set the time. I set both marks at TDC---also check the vaccum hose for cracks and not fitting snug. After I set both marks at top dead center. Start it or try starting it. You,ll have to move the distributor to start(sometimes). Then move the distributor to where it runs best. I don,t know much about this electronic stuff. I do know and found out. Once a motor starts getting mileage on them--parts wear and sometimes you,ll have to set the timing buy ear or have someone listen for you if you are hard of hearing. With the marks being odd one and a half inches--its a good bit. What you also can do to check the chain--without taking it apart is. Set it back on TDC. Take the cap off. Mark where the button points to. Then buy hand. Move the crank in the opposite direction--slowly --until you see the button move. If it has to go one and a half inches before the button moves--more the likely the chain is bad. Also don,t be surprised if it has alot of miles on it. When you put the new chain and gears on it. It will take the slack up in the bottom of the motor and you,ll have to rebuild it. It happened to me. When I started the truck up. It sounded like all the rods were pounding,but I had 285,000 on it. Real good for a old 1964 with a 292. Good luck.

 

[Tiha]

What about inside the distributor, is the mechanical advace stuck open? always advanceing?

Or does the Vaccum advance work properly? Does the plate move? Or is it stuck?

 

[johnnyreb]

What about inside the distributor, is the mechanical advace stuck open? always advanceing?

Or does the Vaccum advance work properly? Does the plate move? Or is it stuck?

Speaking about distributors. Also check for a short. I remember dad and I were working on his car. Had a miss in it. It was the distributor.. Since he,s stuck in 10 degrees--he never mentioned how long he had the vehicle or mileage. Someone could have changed it.The 1 and a half inch. I,m think the chain is bad or. balancer. He never mentioned it how it ran when he got it and later. Mine started looseing power and it had a alot of miles on it. My brother drove his ford pick up hear from Sparta,Illinoise. Running good. Then when we started taking it apart to rebuild. It had 1 tooth on the gear. Plus 2 rods--The taps was taken off with my hand. It also had a good bit of mileage on it. If it has 75,000 miles on it.Look out to replace the timing chain and other parts. Some people are ******* stuff and all that jerking does tear up things and it wears out faster.

 

[johnnyreb]

Listen to Tiha, Miensk ,Rico 330 and I . Go back over it --take your time and double check. That is how you time it. If the mark(s) is 1 and a half inches off---. Try moving it buy HAND. Watch the harmonica balancer--to see if its slipping. If it DOES NOT move. It is the chain has slipped. Then can jump time--ANYTIME.

 

[johnnyreb]

Listen to Tiha, Miensk ,Rico 330 and I . Go back over it --take your time and double check. That is how you time it. If the mark(s) is 1 and a half inches off---. Try moving it buy HAND. Watch the harmonica balancer--to see if its slipping. If it DOES NOT move. It is the chain has slipped. Then can jump time--ANYTIME. When you get aggervated--it is very easy to over look something. It happens to all of us.

 

[MaineBroncoBeast]

I have the truck running with 20 in/hg vacuum and runs well except the timing problem hasn't changed. The timing mark 10 btdc on HB is still flashing near the half circle notch of the timing pointer for the engine to run the best. If I turn the dist to the right of the sweet spot to flash 10 btdc at the timing pointer, the engine vacuum drops and engine runs rough. If I turn the dist more to the left of the sweet spot, the engine vacuum also drops and engine will run rough. The sweet spot is where I have it tightened down. I drove it around and it idles and runs fine.

This is the procedure that I have always used and it's fairly easy to follow.

From 2010... https://www.fullsizebronco.com/threads/how-to-properly-set-the-timing-on-a-302-or-351.168214/

Nothing has changed from my original description of the problem and no errors in the timing process or firing order.

I don't see any indication that the harmonic balancer is bad or slipping... I always use a 15/16" socket and turn the crank by hand, no slipping.

I guess that leaves the timing chain to check?

The engine is brand new in fall 2017 and I put a new HB on it when I installed it. I haven't even put 3000 miles on it yet.
I parked it in 2018 when I sold my big house and bought a nice Hyundai Santa fa Limited. This summer, I went all around the Bronco and did the body work and fixed every mechanical/electrical problem I found.

Thank you everyone

 

[MaineBroncoBeast]

Something to remember is parts wear and you can not always go buy the book Miensk told you right. Now when I set the time. I set both marks at TDC---also check the vaccum hose for cracks and not fitting snug. After I set both marks at top dead center. Start it or try starting it. You,ll have to move the distributor to start(sometimes). Then move the distributor to where it runs best. I don,t know much about this electronic stuff. I do know and found out. Once a motor starts getting mileage on them--parts wear and sometimes you,ll have to set the timing buy ear or have someone listen for you if you are hard of hearing. With the marks being odd one and a half inches--its a good bit. What you also can do to check the chain--without taking it apart is. Set it back on TDC. Take the cap off. Mark where the button points to. Then buy hand. Move the crank in the opposite direction--slowly --until you see the button move. If it has to go one and a half inches before the button moves--more the likely the chain is bad. Also don,t be surprised if it has alot of miles on it. When you put the new chain and gears on it. It will take the slack up in the bottom of the motor and you,ll have to rebuild it. It happened to me. When I started the truck up. It sounded like all the rods were pounding,but I had 285,000 on it. Real good for a old 1964 with a 292. Good luck.

Brand new engine with less than 3000 miles with new harmonic balancer installed at installation time.

 

[johnnyreb]

Brand new engine with less than 3000 miles with new harmonic balancer installed at installation time.

That,s bad. This junk from China is sad. I,m goin through about the same -in the last few years. Good luck.