The Ford Barn

cas3 · 01-12-2017, 12:35 PM

an engine rebuilder told me he indexes the cover for true center to drive the distributor correctly. we do that on model T timers, but i never heard of it on a flathead. am i just showing my ignorance again, or is this how its done?. not sure how you would find center with the drive slot offset! thanks, skip

JSeery · 01-12-2017, 12:46 PM

I've never heard of it.

shoe box Jack · 01-12-2017, 12:49 PM

new to me?? shoe

rotorwrench · 01-12-2017, 01:17 PM

The only adjustment of ignition timing is internal to the distributor on the pre 49 models (except pickups/trucks) and that is limited. I can see making a mark for TDC for the No. 1 cylinder since that can be useful to a degree when performing diagnostics but that would be the only reason I can think of. 8BA family of engines could make a bit better use of that.

Bored&Stroked · 01-12-2017, 01:40 PM

I'd like to see the 'picture' of this special modification . . . as I can't imagine what he is talking about. The drive location of the timing cover bore is in a fixed spot - not way to change it in relation to the cam snout.

Ol' Ron · 01-12-2017, 02:02 PM

Sponsored Links (Register now to hide all advertisements)

You can raise or lower the distributor to affect the gear location of the cam ans distributor drive gear.How once that's set, you set the timing with a light.

40 Deluxe · 01-12-2017, 03:21 PM

Quote:

Originally Posted by cas3

an engine rebuilder told me he indexes the cover for true center to drive the distributor correctly. we do that on model T timers, but i never heard of it on a flathead. am i just showing my ignorance again, or is this how its done?. not sure how you would find center with the drive slot offset! thanks, skip

Is this done to correct some problem, or to merely add a couple hundred dollars to the rebuilder's bottom line?

JSeery · 01-12-2017, 03:24 PM

Adding a TDC mark and indicator is something I do, but really not needed on a stock engine.

tmiller6 · 01-12-2017, 07:56 PM

As a Model T owner, I index my timing cover with a pilot tool. The reason is because the timer rotor is fastened to the camshaft and the timer (distributor housing) with the contacts is a separate piece. If you don't mount the cover co-axial to the camshaft, half the cylinders fire early and the other two fire late.

Since the flathead distributor contains an integral rotor and distributor body, I don't have the same issue with my '41 as I do with the Model T. I just bolted the distributor onto the cover and drove it.

cas3 · 01-12-2017, 09:10 PM

tmiller, thats exactly what i'm talkin about. this guy said just like our T's, the cover has enough slop in the bolt holes that you can move the cover around a bit before you lock it down. like others have said, the dizzy has its own bushing, centered, for the point lobes to spin on, not on the cam itself like the T. he is near me so i'll have to see what he is doing. the guy does a lot of high dollar antique boat motors. could also be a way to get your money!

BillM · 01-12-2017, 09:58 PM

If my memory is correct the hole in the center top of the front cover is slightly smaller than the rest and the bolt for that hole ( or maybe all the bolts) have a shoulder diameter that is a little larger than normal, which serves to align the cover accurately. This is on a 59 block.

flatjack9 · 01-12-2017, 10:01 PM

Quote:

Originally Posted by cas3

tmiller, thats exactly what i'm talkin about. this guy said just like our T's, the cover has enough slop in the bolt holes that you can move the cover around a bit before you lock it down. like others have said, the dizzy has its own bushing, centered, for the point lobes to spin on, not on the cam itself like the T. he is near me so i'll have to see what he is doing. the guy does a lot of high dollar antique boat motors. could also be a way to get your money!

That is a bunch of bull.

JWL · 01-13-2017, 07:00 AM

It is correct there is a full shoulder bolt and .324 reamed cover hole which controls the radial location of the timing cover. There is also a machined shoulder which aligns in the engine block to maintain lateral locations. So, anything other than some sort of timing marking to "center" things is a misunderstanding or a scam.

Bored&Stroked · 01-13-2017, 08:33 AM

Maybe he hasn't figured out that the timing cover mounting/indexing area of the block is round - 7.00" in diameter on the inside and about 8.44" on the outside. Given this, if the timing cover didn't have the flat bottom area to cover the crankshaft, you could rotate it all you want and you'd never change the relationship on how the cam gear drives the distributor - all you'd change is timing.

But - if the guy is talking about ensuring that the timing is accurate - then he'd be checking TDC on the #1 piston and validating that a 'pointer' aligns up with the crank pulley in the proper manner. And he'd just account for any discrepancies in the relationship by moving the pointer, remarking the pulley, etc - he'd do nothing with the timing cover.

But, the original post didn't talk about timing - just drive alignment . . . so who knows.

JM 35 Sedan · 01-13-2017, 08:42 AM

Quote:

Originally Posted by BillM

If my memory is correct the hole in the center top of the front cover is slightly smaller than the rest and the bolt for that hole ( or maybe all the bolts) have a shoulder diameter that is a little larger than normal, which serves to align the cover accurately. This is on a 59 block.

What Bill is posting is exactly what I was thinking as I read all the posts from the beginning of this thread. The timing gear cover bolts are special and intended to align the cover. I've often seen this mentioned in Ford service bulletins and other publications on Ford flathead engines.

cas3 · 01-13-2017, 11:23 AM

its a 59 block i am referring to, sorry i should have posted that. i agree with all, and i have known the bolts are special shouldered, same as the six shift tower bolts,and the preasure plate bolts? JWL, i didnt see that the center one is special, i'll have to look. at any rate, i dont see how you could move that cover around at all.

flatjack9 · 01-13-2017, 01:14 PM

I wonder how many flatheads that rebuilder has actually built?

Bored&Stroked · 01-13-2017, 04:56 PM

Quote:

Originally Posted by flatjack9

I wonder how many flatheads that rebuilder has actually built?

He's just getting ready to build a REALLY EXPENSIVE one! LOL

dude · 01-13-2017, 07:34 PM

sounds like a little over kill.

01-12-2017, 12:46 PM	#2
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: index the timing cover? I've never heard of it.

01-12-2017, 12:49 PM	#3
shoe box Jack Senior Member Join Date: Dec 2012 Location: Kingston Ontario Canada Posts: 251	Re: index the timing cover? new to me?? shoe

01-12-2017, 01:17 PM	#4
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,425	Re: index the timing cover? The only adjustment of ignition timing is internal to the distributor on the pre 49 models (except pickups/trucks) and that is limited. I can see making a mark for TDC for the No. 1 cylinder since that can be useful to a degree when performing diagnostics but that would be the only reason I can think of. 8BA family of engines could make a bit better use of that.

01-12-2017, 01:40 PM	#5
Bored&Stroked Senior Member Join Date: Jan 2011 Location: Central Ohio Posts: 5,062	Re: index the timing cover? I'd like to see the 'picture' of this special modification . . . as I can't imagine what he is talking about. The drive location of the timing cover bore is in a fixed spot - not way to change it in relation to the cam snout.

01-12-2017, 02:02 PM	#6
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,857	Re: index the timing cover? Sponsored Links (Register now to hide all advertisements) You can raise or lower the distributor to affect the gear location of the cam ans distributor drive gear.How once that's set, you set the timing with a light.

01-12-2017, 12:35 PM	#1
cas3 Senior Member Join Date: Jan 2011 Location: sw minnesota Posts: 4,568	index the timing cover? an engine rebuilder told me he indexes the cover for true center to drive the distributor correctly. we do that on model T timers, but i never heard of it on a flathead. am i just showing my ignorance again, or is this how its done?. not sure how you would find center with the drive slot offset! thanks, skip

01-12-2017, 03:24 PM	#8
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: index the timing cover? Adding a TDC mark and indicator is something I do, but really not needed on a stock engine.

01-12-2017, 07:56 PM	#9
tmiller6 Senior Member Join Date: Jul 2010 Location: Livonia, MI Posts: 197	Re: index the timing cover? As a Model T owner, I index my timing cover with a pilot tool. The reason is because the timer rotor is fastened to the camshaft and the timer (distributor housing) with the contacts is a separate piece. If you don't mount the cover co-axial to the camshaft, half the cylinders fire early and the other two fire late. Since the flathead distributor contains an integral rotor and distributor body, I don't have the same issue with my '41 as I do with the Model T. I just bolted the distributor onto the cover and drove it.

01-12-2017, 09:10 PM	#10
cas3 Senior Member Join Date: Jan 2011 Location: sw minnesota Posts: 4,568	Re: index the timing cover? tmiller, thats exactly what i'm talkin about. this guy said just like our T's, the cover has enough slop in the bolt holes that you can move the cover around a bit before you lock it down. like others have said, the dizzy has its own bushing, centered, for the point lobes to spin on, not on the cam itself like the T. he is near me so i'll have to see what he is doing. the guy does a lot of high dollar antique boat motors. could also be a way to get your money!

01-12-2017, 09:58 PM	#11
BillM Senior Member Join Date: May 2010 Location: Everett, WA Posts: 504	Re: index the timing cover? If my memory is correct the hole in the center top of the front cover is slightly smaller than the rest and the bolt for that hole ( or maybe all the bolts) have a shoulder diameter that is a little larger than normal, which serves to align the cover accurately. This is on a 59 block. __________________ My web page: http://myplace.frontier.com/~wgmumaw/

01-13-2017, 07:00 AM	#13
JWL Member Emeritus Join Date: May 2010 Location: Fitzgerald, Georgia Posts: 2,204	Re: index the timing cover? It is correct there is a full shoulder bolt and .324 reamed cover hole which controls the radial location of the timing cover. There is also a machined shoulder which aligns in the engine block to maintain lateral locations. So, anything other than some sort of timing marking to "center" things is a misunderstanding or a scam.

01-13-2017, 08:33 AM	#14
Bored&Stroked Senior Member Join Date: Jan 2011 Location: Central Ohio Posts: 5,062	Re: index the timing cover? Maybe he hasn't figured out that the timing cover mounting/indexing area of the block is round - 7.00" in diameter on the inside and about 8.44" on the outside. Given this, if the timing cover didn't have the flat bottom area to cover the crankshaft, you could rotate it all you want and you'd never change the relationship on how the cam gear drives the distributor - all you'd change is timing. But - if the guy is talking about ensuring that the timing is accurate - then he'd be checking TDC on the #1 piston and validating that a 'pointer' aligns up with the crank pulley in the proper manner. And he'd just account for any discrepancies in the relationship by moving the pointer, remarking the pulley, etc - he'd do nothing with the timing cover. But, the original post didn't talk about timing - just drive alignment . . . so who knows.

01-13-2017, 11:23 AM	#16
cas3 Senior Member Join Date: Jan 2011 Location: sw minnesota Posts: 4,568	Re: index the timing cover? its a 59 block i am referring to, sorry i should have posted that. i agree with all, and i have known the bolts are special shouldered, same as the six shift tower bolts,and the preasure plate bolts? JWL, i didnt see that the center one is special, i'll have to look. at any rate, i dont see how you could move that cover around at all.

01-13-2017, 01:14 PM	#17
flatjack9 Senior Member Join Date: May 2010 Location: Oshkosh, Wi Posts: 4,526	Re: index the timing cover? I wonder how many flatheads that rebuilder has actually built?

01-13-2017, 07:34 PM	#19
dude Senior Member Join Date: May 2010 Location: Kansas Posts: 334	Re: index the timing cover? sounds like a little over kill. __________________ [QUO[/QUOTE]no matter where you are,or where you're at, there you are...