Rebuilt Flathead Problems.

Don´t shoot the messenger...but that engine has to come apart completely...so you can check the rest of it.
I wouldn´t run it...cheaper to adress any other problems now then when it blows up on you.
Sorry for the bad news.
 
Another reason to pull the heads/valves: Using longer (Chevy) valves locates the keeper groove lower, making spring pressure less. I don't see any shims on the valves pictured. I used the Zephyr springs and still had to put at least .060 shims in all of them to get around 50# seat pressure. .
 
Now if you had an engine with no marks on the gears, whow would you proceed . Well you could just use the Split overlap for a quickie, or you could degree the cam in. If you have the numbers. It's been a very interesting thread.
 
Hang in there Gordon, your getting there! I do think there is merit in checking everything out from the get/go. I would want to check the bearing clearances, the ring gaps, and so on. I agree it is almost impossible for the spring seat pressure to be correct with the current setup you have, so there are things than need to be straightened out.
 
I guess the chamfer on crank gear would be to clear a radius ground on crank?

So it would not be advisable to leave that crank gear on backwards for a sharp edge to bite into crank?
 
If the crankshaft gear is on backwards looks like you will have to pull the pan and you may find your dot on the other side.
Some times leaving the key out then line up the dots and then slide the keyway in place. I would do the job right and get it over.
 
I'm glad we're getting somewhere.

My only concern right now is regarding the gear. If it is on backwards, the relationship between the keyway and the teeth may not be the same as it is when viewed from the front. It also may not be seating against the crank correctly.

If you want to run it as it is, please make double sure you have the correct tooth marked. It's difficult from here, thousands of miles away looking at a monitor.

If you decide to drop the pan and pull the gear, (might only need to lower the pan slightly) It can be closely inspected and the correct tooth identified for the mark.

I'd be strongly leaning towards removing the motor and carefully dismantling it. It can then be put back together methodically with any areas of concern checked along the way.

Hopefully, other than the cam timing issue, all may be well. If it is, you would still be able to say you built it yourself instead of hoping it was put together right by someone not familiar with these old lumps.

Mart.
 
Mart said:
Ok. Look at this pic:

342477


Can you see the the original timing mark at 90 degrees to your mark? That's funny, isn't it? With the cam gear marks aligned No.1 should be at TDC. The timing mark should be aligned with the timing pointer.

Where is the timing pointer on an 8BA? check this pic.
001.jpg


It's not where the timing mark is, it's roughly in line with No.1 cylinder.

Your gear is either fitted wrong or marked wrong.

I'll repeat:

Your gear is either fitted wrong or marked wrong.


Ignore any comments about distributors, springs and the cam even, the first thing to establish is the relationship between the crank, the keyway, no.1 tdc and the mark on the gear.

All the other things can be looked at in turn once the correct cam timing has been established.

Mart.
Click to expand...

Mart, it looks to me like a sbc guy didn't know how the timing marks worked and setup the cam to be lined up with the sbc cylinder as #1 :eek:


Mart said:
I'm glad we're getting somewhere.

My only concern right now is regarding the gear. If it is on backwards, the relationship between the keyway and the teeth may not be the same as it is when viewed from the front. It also may not be seating against the crank correctly.

If you want to run it as it is, please make double sure you have the correct tooth marked. It's difficult from here, thousands of miles away looking at a monitor.

If you decide to drop the pan and pull the gear, (might only need to lower the pan slightly) It can be closely inspected and the correct tooth identified for the mark.

I'd be strongly leaning towards removing the motor and carefully dismantling it. It can then be put back together methodically with any areas of concern checked along the way.

Hopefully, other than the cam timing issue, all may be well. If it is, you would still be able to say you built it yourself instead of hoping it was put together right by someone not familiar with these old lumps.

Mart.
Click to expand...

regarding your post about the gears being in relation when spun... I would guess if the gear is chamfered heavily for the crank fillet then it will be too far forward without the chamfer. if the gears are not in line with each other the cam timing will be out of alignment with the gear. JWL talks about checking the cam clearance to the front cover being in the area of .009 max if memory serves. allowing the cam to move forward or back allows the cam to rotate relative to the crank. the same movement would apply to the crank gear. this could advance or retard the cam.
 
Guys I appreciate all the assistance. Blue stuff is grease.

I noticed last night while looking at this setup that the front edges of the pan gasket pulled away when the timing cover came off so Ill have to pull the pan to put new gaskets on there. When I do that I will see if I can get this crank gear off and put it on the correct way. I saw some stuff about getting the old one off and I'll get a new one and put it on correctly if need be. I have new head gaskets so at the same time I will pull all the valves again and do whatever needs to be done to correct that. It'll make the cam easier to reposition anyway won't it? I don't know that I am going to pull the crank and pistons and check stuff like the ring gap. I'll consider that when I get to pulling the pan off. As we are heading into the holiday season and I am going to be traveling for the next 3 weeks progress on this is going to be halted until I get back in town. I do appreciate all the suggestions because there is literally zero persons in my area interested in running or building an engine this old. I have 1 friend in the area into old cars but he is running a Willys with a blown 468 in it so isn't much help with what I am doing. I'll start updating again as soon as I get back on it and will check in on this as often as possible. I will still need direction on solving the valve issues.
 
Gordon thanks for your posting and to all the members who have tried to help along the way. This has been a very interesting read as I have just started on my first flathead and this has been very valuable information.
 
I think this experience shows the need to run an engine before installing it in the chassis. And just for your info, that crank gear does not come off easily. It takes a strong puller and I usually give it a little heat to aid in the pull.
 
A couple of times members here told me I should post my troubles so others could benefit and I'm glad they have helped. Your welcome buzz4041.

flatjack9 I have torches so can and will put heat to it when I go to give it a pull. If that doesn't work I have seen posts of folks giving the gear a good whack between teeth with a sharp chisel and it splits and then can be pulled off. In which case I will get a new one and put it on. Your correct about running an engine before installing but I don't have a test stand. It went from the engine stand to the chassis. In the future I will purchase no engine unless I get to see and hear it run first!
 
Gordon, good for you for sticking with it and sorting through all the suggestions thrown at you at one time. With your patience and determination I feel sure you will see this through. I'm looking forward to continuing this journey with you. Merry Christmas and enjoy your holidays.
 
I say these are nothing more than glorified lawn mower engines but even those have gotten more high tech. There are some flathead nuances that a rebuilder should know about, such as grinding a radius on the crank but this is a real rookie mistake for anyone who knows how to assemble an engine. If this guy were building an interference engine he would be paying big bucks to fix it. I do not see this as lack of knowledge as much as sloppy workmanship.
 
GordonC said:
A couple of times members here told me I should post my troubles so others could benefit and I'm glad they have helped. Your welcome buzz4041.

flatjack9 I have torches so can and will put heat to it when I go to give it a pull. If that doesn't work I have seen posts of folks giving the gear a good whack between teeth with a sharp chisel and it splits and then can be pulled off. In which case I will get a new one and put it on. Your correct about running an engine before installing but I don't have a test stand. It went from the engine stand to the chassis. In the future I will purchase no engine unless I get to see and hear it run first!
Click to expand...

Hindsight here, but when you hit a snag like this, it's often quicker and less frustrating to just pull the engine back out right away. Makes it easier to check everything out and get it back together without leaks.

Sometimes, "the long way around the barn is the quickest way home", plus you avoid that mean bull!
 
Frank Miller, it can both I guess. Either way I have ended up with a whole lot of issues I now have to fix and even though I tried hard to not be in this situation, I am. So I'll work through it with everybody's help. FYI I used to live in Westborough right off rt.9 by the state hospital and Lake Chauncy.
 
GordonC said:
Frank Miller, it can both I guess. Either way I have ended up with a whole lot of issues I now have to fix and even though I tried hard to not be in this situation, I am. So I'll work through it with everybody's help. FYI I used to live in Westborough right off rt.9 by the state hospital and Lake Chauncy.
Click to expand...

where do you live now?? if you moved to western mass I can help! i'm not much further ahead than you are now in your flathead assembly process...

also, after reading ronnieroadsters reply (second post) I went back and looked at your pictures of the gear alignment. it appears that your crank and cam gears mesh nicely. if that is the case you don't need to pull the crank gear at all. just stamp it and move on! pull the valves out to check spring pressures. with the valves out you can unbolt the cam gear, set it to the correct point and rotate the cam to match. easy peasy!
 
Last edited:
revkev6 I moved down to Wilmington NC about 13 years ago. Just got too tired of the short summer, long winters, and too much snow shovelling! Don't have any of that down here and I can actually work in the shop almost all year round without heat. I have to pull the pan anyway so I will decide then if I need to pull the gear or not. If it fights me too much I may just mark it and move on...we will see.
 
You must log in or register to reply here.
Back
Top