Rebuilt Flathead Problems.
 

It has been suggested by a couple of folks that I should post up my problem with my rebuilt flathead. So here goes. This may get a little long winded so bear with me please.

I have a 1950 Ford 8ba that was rebuilt at a local engine rebuilder. He did all of the machine work and assembly to deliver me a completed short block approximately a year ago. I provided all new parts except for the crank and rods. I put everything else on the engine, heads, intake and so on... I recently installed it into my A roadster and got it ready to fire up. I have all new everything here, new battery, new starter, new flywheel, fuel pump, lines, Bubbas distributor, everything. I set the TDC by putting my finger over #1 plug hole and when I felt compression I rotated it until the timing dot on the pulley aligned with the pointer on the cover and stopped it there. I put the distributor in with the rotor pointing to the #1 plug at approximately 12 o'clock on the distributor. I then ran the plug wires going clockwise using the normal flathead firing order, 15486372. Added my oil and zinc via the remote filter lines. Cranked it with no plugs in to build some pressure. Have oil showing in the oil gauge line. I then attempted to get it to fire and nothing. Its got gas, its got spark and turning over real nice. Advanced the distributor nothing. Retarded it, nothing. No kick, no backfire except for just 1 time. Other than that it just spins. Took a compression reading and all cylinders are at 50 lbs. Which was odd to me. Thought maybe valves were hanging open so I went back through setting the lash and all of the valves were within .003 of where they should have been. Tried again to start with no luck. Decided to pull the timing cover off to check the crank and cam gears to see if they are set up properly with the engine still sitting at what I thought was TDC on compression stroke. Looked at cam gear and can see its dot at about the 7 o'clock position. No dot showing on the crank gear? I have spun this crank 360 degrees multiple times and cannot find a mark on it anywhere to indicate where the initial crank position was set. As I understand it the cam dot and the crank dot are aligned at 12 and 6 respectively and from there you should be good to go. I am not sure the cam gear is installed properly either as the machinist has used socket head allen screws to install it?

So I am at a point where I need some direction on how to proceed. I can pull the heads, the intake, drop the oil pan and so on, but wanted to see if I can somehow straighten this mess out without doing all that and get this running. Now before you say take it back to the guy who did the work he has moved his business and I found some other things done to the engine that indicate to me he shouldn't have touched it in the first place so I have no faith in his ability to correct whatever he did to it.

I can take whatever pictures might help and post them up but I need help on this one.

Re: Rebuilt Flathead Problems.
 

Looks like the rebuilder put the crank gear on backwards! Thats the only reason to not see a dot on the crank gear. Its possible to correct this without removing the crank gear which is near impossible to do with the crank installed. First I would be sure the front of the crank gear is flush to the front of the cam gear if it is then i would move on to the next step. The next step requires the right side head to be removed so the piston can be located at top dead center. When this step is completed now a timing dot can be marked onto the crank gear.
The final step will be a bit more difficult moving the cam shaft to the proper position so the cam gear dot lines up with the crank gear. This step is difficult due to the fact you need to move the cam without the cam gear bolted in place turning the cam with the valve spring pressure is the hard part. To rotate the cam to the correct location I would use two long 6/16 fine thread bolts placed in two of the cam bolt holes this will give a leverage point to turn the cam which at the same time will also be working the valves. The cam gear bolt pattern is not even spaced so the proper location of the cam will be found as you check the bolt pattern to the pattern in the cam gear.
This is not a simple job but also not impossible with a little effort you will solve the problem.
Ronnieroadster

Re: Rebuilt Flathead Problems.
 

If he installed the crankgear outside in the dot is now facing the engine...
Even if the timing is way off some kind of backfiring would happen...or atleast i think so...and you have a good spark ?

Re: Rebuilt Flathead Problems.
 

I agree with Ronnie Roadster . The cams in wrong.!!! Been there done that, just had one here in indy when the customer said it has spark, i asked does it pop or backfire . He said no. Found the cam installed wrong after a few weeks of discussion....:eek:

Re: Rebuilt Flathead Problems.
 

You should be able to get your no 1 piston somewhat TDC on no 1 without removing the head.

Certainly close enough to a single tooth tolerance on the timing gear .

Put a chalk mark on the crank pulley to a mark on the block.

Rotate the engine and look down no 1 spark plug hole until you see both valves rocking , this is where the piston should be on TDC on the backstroke.

When they are rocking , your chalk mark should line up with where you marked it.

Re: Rebuilt Flathead Problems.
 

Another way to find TDC is with a zip tie. Check this link out:

http://www.jalopyjournal.com/?p=10940

Once you have determined TDC, use your thumb over the spark plug hole to make sure it is coming up to the compression cycle for number 1 cylinder.

Re: Rebuilt Flathead Problems.
 

I have good spark. New coil, new wires, new plugs, and a Bubbas distributor. I don't think the problem lies there.

I have a strong feeling that what is wrong is the cam timing but wasn't sure how to go about fixing it. Is the only way to determine TDC to pull the head? I can look right down through the plug hole on the piston in the cylinder so can see when it stops moving if need be.

Bubba you were nice enough to reply to my email about a week ago asking about point gap on the dist I got from you. Thanks.

Re: Rebuilt Flathead Problems.
 

There was a similar thread recently on the same subject.

I'm not that well up on the 8BA, but does it have a timing mark and pointer? If so, when the pointer is lined up, the valves should be "rocking" (exhaust just closing/inlet just opening) on either no1 or no6 cylinder.

If neither are rocking, then further investigation is justified.

I always look upon this as a "sanity check" when troubleshooting an engine.

Oh yeah, when No.6 cylinder valves are rocking, No.1 should be firing.

You can apply this to any engine, you just look at the firing order and the next one after the halfway point in the order is No.1 cylinder's companion. The pistons are at tdc at the same time. One or the other will be firing, and the valves rocking on then other.

It would have been good if you could have verified the timing mark when the head was off, preferably by a solid stop method.

That said, if the engine hasn't run, you ought to be able to pull the head and work out what is going on. You should be able to refit it with the same gasket if it comes off cleanly.

Mart.

Edit: I wrote this before reading the two replies above. You can see the exhaust valve through the plug hole and possible the edge of the inlet. You can't see the piston on a flathead, only the valve.

You could use the cable tie method to determine TDC. You'd get it close enough for the sanity check described above.

Re: Rebuilt Flathead Problems.
 

Follow Rons suggestions, When I tine the cam on most street engines I wlway check for split overlap. It's a simple thing to d. bring the #1 piston to TDC by the dot. both valves should be open aprox the same amt. If not, give the cranl another trip around and they should both be open. If they are not, you have a problem
Another Ron.

Re: Rebuilt Flathead Problems.
 

Also, when I put my finger over the plug hole and turned the motor over I got compression and then rotated the crank just a small amount to get the timing cover pointer and pulley dot to align. Once I did that here is a pic of what I got. It looks to me as if the cam timing is off. So if I leave it set so its on compression on #1 and the marks on the pulley and the pointer are aligned all I should have to do is rotate the cam gear/cam until the dot aligns at 6 o'clock. Now I may have to remove the gear and rotate the cam separately and then reinstall it to get it lined up but wouldn't that work?

Re: Rebuilt Flathead Problems.
 

There is no need to pull the head to find TDC. That's a lot of work for no gain.

Look at the link in my post #6. You slide the head of a large zip tie in the spark plug hole, slowly rotate the engine until it stops and make a mark, rotate in the opposite direction until you hit the stop and make another mark. Half way between the two marks is TDC. This same method is used for OHV motors using a hard adjustable stop that is threaded into the spark plug hole. This of course won't work with our flatheads but the zip tie or similar will.

Re: Rebuilt Flathead Problems.
 

Whoops forgot the picture! The picture shows how I found the timing after I set the #1 cylinder using the finger method to determine compression. I then aligned the timing cover pointer and pulley dot. The temp pointer in the picture is pointing to the dot on the pulley. I didn't want to rotate the motor without some reference/indictor as to where the dot was before I pulled it apart.

Re: Rebuilt Flathead Problems.
 

From the previous thread mentioned above here is a link to the picture of an 8BA crank gear showing the dot.
https://www.fordbarn.com/forum/attac...9&d=1510707802

the thread is here: https://www.fordbarn.com/forum/showt...=233257&page=3

the picture is on post no. 43.

Re: Rebuilt Flathead Problems.
 

glennpm and others I am digesting this as fast as I can! Give me a little bit to sort through these suggestions and see what I can find out.

Re: Rebuilt Flathead Problems.
 

One good thing you have a dot on crankshaft, so that's TDC
Now just turn the crankshaft till the intake opens and mark with chalk at 6 o'clock,turn in the way the engine turns clock wises.
That way to can see how far you are out of time.
The crankshaft should be at 12 0clock or the dot. The marks on gears should with in 2or3 teeth.

Re: Rebuilt Flathead Problems.
 

You can also put a dog leg in a piece of wire such as a 1/16 brass welding rod feed that into top of the piston ,with a wrench rotate it until you are at TDC then mark it with some masking tape. As has been said check through the plug hole ,Or I would remove the inlet manifold and observe the sequence of valve action .As a quick check, On compression stroke both fully closed at TDC ,Ted

Re: Rebuilt Flathead Problems.
 

Hi Gordon, you MUST establish the 2 marks on the timing gears, this is the very first item to look for, once you've done that you can move forward!

Thanks, Gary in N.Y.

P.S. I believe the timing marks are probably on the gears just difficult to see, especially the crank gear. Judging by the photo I also don't believe the bottom gear to be on "backwards", there's a huge chamfer on the backside of that gear to clear the heavy radius from the snout to the face of the front main. It is large enough to stop both gears from being even with each other in the front.

Re: Rebuilt Flathead Problems.
 

I'm remembering the other thread now. The "take home" message was the dot should be on the third tooth round from the keyway.

Re: Rebuilt Flathead Problems.
 

Some of those crank gears have the dot half way into the recess instead of on the tooth so only part of the friggin thing shows and the slinger is in the way. The gear can go on backwards too and it's so close to the main cap it would be hard to see the dot and it won't be in the correct placement for cam timing if it is. There was a purpose made puller for those gears so it could be changed without removing the crank but not that many folks have them now days.

Re: Rebuilt Flathead Problems.
 

Guys I think I found it!! Here is a pic if I can get the darn thing to load.... interestingly enough the cam gear is almost exactly 180 degrees off from this dot. For some reason pictures are rotating 90 degrees on me when I upload them to this site. Doesn't do that on the HAMB?

Re: Rebuilt Flathead Problems.
 

Now your valve timing is good your ign is out 180

Re: Rebuilt Flathead Problems.
 

A cam can appear to be 180 out - as it will ALWAYS be 180 degrees away from the crank dot at one point - as it turns at half speed. When the crank dot is UP, in one case the cam dot aligns, rotate the crank 360 degrees and the cam dot will be straight up at the top - 180 degrees out.

Hopefully I'm making sense.

B&S

Re: Rebuilt Flathead Problems.
 

What do you mean by almost?

At that point , it should be exactly 180 out.

Re: Rebuilt Flathead Problems.
 

Hi Gordon,

Look at the gears in post #17. The cam turns 1/2 a revolution for a complete 360 degree revolution of the crank gear. In the picture above assume the crank gear is as shown. A full turn of the crank gear would yield the cam gear with dot 180 degrees out or on top in this picture. Is that what you are seeing?

Re: Rebuilt Flathead Problems.
 

Ok. I rotated the crank gear 360 degrees until the dot was at the 12 o'clock position again and the dot on the cam gear is now on the same location as the dot on the crank gear. It looks like it is set up correctly? If the gear is put on the cam correctly this thing should have fired?

Re: Rebuilt Flathead Problems.
 

pooch I meant by eyeball it looked approximately about 180 out.

Re: Rebuilt Flathead Problems.
 

Yes, alignment is correct.

Have you checked to make sure that your ignition wire to #1 and of course the rest in the right firing sequence, is on the compression stroke?

Re: Rebuilt Flathead Problems.
 

glennpm I need to put the timing cover back on once I am sure the cam gear is mounted properly and the timing is correct. Then I can go back to checking the distributor and the wiring. I am reasonably sure I had it correct.

Re: Rebuilt Flathead Problems.
 

There is some conflicting information out there. Be sure you know where the rotor is located inside the distributor when you are establishing No. 1 in the firing order. These two diagrams are 180 to each other.

Re: Rebuilt Flathead Problems.
 

On my 8BA the rotor points to number 1 terminal on the cap when number 1 piston is a TDC and the timing marks line up.

Re: Rebuilt Flathead Problems.
 

Pic 17 shows how the marks are correct.
The keyway is TDC
What they are doing is retarding the TDC 2 1/2 teeth.
This is the start of the cam getting ready to open the intake.
If you have the dots lined up that's correct.
That's cam timing. now turn 180 and get #1 firing.
If the cap is marked#1 the rotor should be 6 o'clock +OR_

Re: Rebuilt Flathead Problems.
 

I would still look down no 1 plug hole and get valves rocking on the backstroke and see if your mark is exactly as you posted it post 20.

Then you can diss the cam timing and move on .

Rotate the crank 360 so that both marks are lined up.

This is TDC firing on #1.

Then check your plug wires are correct.

After you are sure you have cam and igntion timing correct, and a good spark at plugs, are you pouring a little gas down carby and then spinnng engine over with throttle wide open?

Re: Rebuilt Flathead Problems.
 

So from here-on, verifying the cam position is best done when the mark on the 8BA pulley is aligned with the pointer at TDC on the EXHAUST stroke where you can see the valves rocking like Mart described in post #8. Here's an excerpt from Walt Dupont from a long-ago post that walks you through it...

"With the intake off, turn the engine over (right hand rotation) watch the exh. valve on no. one piston (front piston on right side) watch the exh. valve open and close, just before it closes the intake will start to open, you can rock the crank back and forth and both valves rock back and forth, both valves will be off the seat, that's called valve overlap, no. one piston should be on TDC exh. stroke. If the timing cover is on the pointer should line up with the mark on the front pulley. If the mark is off quite aways, the timing gears are not lined up. Could be the dot on the gear is punched in the wrong place. Walt"

Lonnie

Re: Rebuilt Flathead Problems.
 

Ok.. so you have the cam that appears to be lined up but we still have to figure out why you are reading only 50lbs of cranking pressure. One question that scares me... if u say he s houldnt have been working on a flathead is did he do the valves correctly? 45 vs 30 degree valves... or grinding the valve seats parallel to the deck.... these are harder to fix.

Re: Rebuilt Flathead Problems.
 

Ok guys all good info now. I am going to have to pull the intake to be able to get a good look at what the valves are doing and when they are doing it in relation to where the cam and crank marks are. I will be doing that tomorrow and see what I get.

Pooch I initially used a shot of starting fluid until I could see gas squirting down the throat of the carburetor. I have 5 1/2 lbs pressure on the line feeding the carb and the fuel is recent as well. Not some junk that has been sitting in the tank for a while.

Re: Rebuilt Flathead Problems.
 

you may have washed the oil off the cylinders causing low comp.if your sure cam timing and ignition timing are correct pull the plugs makr sure they are dry.oil the cylinders and try pull starting it ive done it many times to get one going.

Re: Rebuilt Flathead Problems.
 

If the dots and jetway are like 17 pic do compression check and you will see it's ok

Re: Rebuilt Flathead Problems.
 

I don't agree with this at all. I have done two fresh rebuilds in the last year and have had no problems getting them started. I set the timing with an ohmeter, filled the bowls through the vent, and both started almost immediately. In my experience, if you have trouble starting a fresh engine, there is a problem. Find and solve that problem rather than resorting to extreme methods. I found this out the hard way many years ago. Luckily, it didn't cost me a lot, because it was a snowmobile engine. I honed it and put in new rings, bolted the rest together and tried to start it. I almost tore my arm off and resorted to dumping gas in the carb and sprayed staring fluid until the cows came home. Finally it fired and ran. For 30 seconds. Then it self-destructed. It turned out to be improperly installed piston rings. A fresh engine should not be a problem to start. Your method is OK with "field cars" I guess, but I wouldn't do it with a fresh build.

Re: Rebuilt Flathead Problems.
 

I would take a look at the camgear...original bolts and the locking washer perhaps while you have it apart...and just to be sure check so the camgear is on right matching the holes in the camshaft.

Re: Rebuilt Flathead Problems.
 

Of the two diagrams in post number 29. As you stand on the passenger side viewing the distributor cap, number one should be on the bottom. Of course it can be made to work anywhere, as long as you have the rotor in sync with your chosen position. 1 at the bottom is stock.