Here’s a whole ‘nother question

J

jeepguy1948

Well-known member
Here’s a whole ‘nother question

8BA motor and no fuel pump or push rod. The motor was this way when I got it. I have learned that the hole/bushing must be plugged to keep large amounts of oil spewing upwards (it never has been but it will be now). It was not apparent to me at first (before I drilled the bushing out) but i can now see that the oil tube extends on into that hole (apparently to oil the rear cam bearing). The bushing was already drilled out before I noticed the hole so I don’t know for certain if there was a hole in the wall of the bushing for it or instead, the bushing plugged/blocked the hole. It appears to me that that is the only way that the rear cam bearing gets oil so it seems that there had to be a hole in that bushing but I’m surprised I never saw it. If things go as they usually do this post will generate more questions that it does answers. I’ll do my best to answer any questions but please try and answer the questions that can be answered along with the questions.

it’s hard to imagine that everything worked ok with that pushrod bushing wide open to the top it seems that that would have a major impact but the oil pressure was very good and the cam and bearing look good (the cam lobes are bad however so this cam is being replaced with a new Max-1) I wasn’t planning to replace the cam bearings as they only have about 1,000 miles on them and they look good. Should I get the tool and replace the bearings?
 
Re: Here’s a whole ‘nother question

I think that the pre-49 motors required you to plug the passage if you did not have the fuel pump rod in there. Then in '49 the blocks oil passages were redesigned so that you no longer had to plug the fuel pump hole. I read that somewhere and then I had a stroke so I would definitely verify this with someone else. Most of the old stuff I still remember, it's what I did five-minutes ago that I can't figure out.
 
Re: Here’s a whole ‘nother question

Flathead Fever said:
I think that the pre-49 motors required you to plug the passage if you did not have the fuel pump rod in there. Then in '49 the blocks oil passages were redesigned so that you no longer had to plug the fuel pump hole. I read that somewhere and then I had a stroke so I would definitely verify this with someone else. Most of the old stuff I still remember, it's what I did five-minutes ago that I can't figure out.
Click to expand...

Flathead Fever is correct, based on my experience.
 
Re: Here’s a whole ‘nother question

While the latter flathead engines oil pressure will not show much of an oil pressure loss when the fuel pump push rod is removed if the engine is in good shape there is a still a loss in delivery. The latter fuel pump push rod bushing has an oil hole in the bushing which lubricates the push rod. This oil hole is in the main oil delivery passage of the block.

While the opening is not as big as the earlier blocks when the push rod is removed there still is a bit of loss in pressure and delivery if the top of the push rod hole is left open. Usually about a 10 pound reduction has been noticed.
Ronnieroadster
 
Re: Here’s a whole ‘nother question

Flathead Fever said:
I think that the pre-49 motors required you to plug the passage if you did not have the fuel pump rod in there. Then in '49 the blocks oil passages were redesigned so that you no longer had to plug the fuel pump hole. I read that somewhere and then I had a stroke so I would definitely verify this with someone else. Most of the old stuff I still remember, it's what I did five-minutes ago that I can't figure out.
Click to expand...

This is wrong information, No need to plug anything when removing the pushrod from an early engine. 8BAs had a small hole in the bushing,
 
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Re: Here’s a whole ‘nother question

jeepguy1948 said:
8BA motor and no fuel pump or push rod. The motor was this way when I got it. I have learned that the hole/bushing must be plugged to keep large amounts of oil spewing upwards (it never has been but it will be now). It was not apparent to me at first (before I drilled the bushing out) but i can now see that the oil tube extends on into that hole (apparently to oil the rear cam bearing). The bushing was already drilled out before I noticed the hole so I don’t know for certain if there was a hole in the wall of the bushing for it or instead, the bushing plugged/blocked the hole. It appears to me that that is the only way that the rear cam bearing gets oil so it seems that there had to be a hole in that bushing but I’m surprised I never saw it. If things go as they usually do this post will generate more questions that it does answers. I’ll do my best to answer any questions but please try and answer the questions that can be answered along with the questions.

it’s hard to imagine that everything worked ok with that pushrod bushing wide open to the top it seems that that would have a major impact but the oil pressure was very good and the cam and bearing look good (the cam lobes are bad however so this cam is being replaced with a new Max-1) I wasn’t planning to replace the cam bearings as they only have about 1,000 miles on them and they look good. Should I get the tool and replace the bearings?
Click to expand...
The rear cam bearing and crank bearing are oiled directly from the oil pump. There is a passage for the oil to go around the pushrod bushing. Oil is fed from the rear of the engine. You need that bushing in there or you will have a huge oil leak. No need to replace those bearings. I hope you didn't drill that bushing out with an oversize drill.
 
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Re: Here’s a whole ‘nother question

Yes I did drill it out with an oversized drill bit. I was drilling it out so that I could thread the whole for a tap. The bushing, whatever it’s made of was simply too hard for me to get a tap to bite. The hole I drilled stops approx 1/4-3/8” from the bottom but it does get into the passage. So, as it sits, I can plug the top, and the bushing ID is still intact at the bottom but if there is more required than what I am attempting to describe needed I am going to need some help sorting that out. Where would be the place to buy a replacement bushing and what is the part number for the correct bushing for an 8BA? I can’t risk getting the wrong one. I appreciate all the help, I would be dead in the water.
 
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