The Stovebolt Site Forums The Shop Area Engine Shop dizzy won't go

Am I missing a part? 58 235---can't get the dizzy to go all the way down. It is indexing the oil pump and cam. I've tried the one that came out plus a second mallory that I have. Same problem. Looks like it's about 1/4 inch shy of sitting on the block.It's a new pump that had the same M45 number on the housing but I did not check them side by side and yes the pan is on and all buttoned up

I'd make sure it IS going all the way down. Use a long thin screwdriver or a small rod that will fit to the bottom of the slot in the oil pump shaft and mark it even with the block distributor hole surface. Now hold one end of that marked rod agaist the bottom of the distributoe mount flange and see if the mark is shorter or longer than the end of the shaft. If it's longer then it's not going all the way down and if it's shorter then the dizzy shaft is bottoming out in the oil pump drive and not letting the dizzy seat. The factory 235 dizzy has a collar that you can loosen a stovebolt and adjust the height.

ok I did the screwdriver test. It indicates that the dizzy should go all the way. The problem is the collor below the drive gear contacts the top of the pump shaft preventing it from going that last 1/4 inch. I see that I can adjust the plate on the dizzy but I'm wondering why when it's all the same except for the pump. My concern would be that the drive gear is not all the way seated and could cause a problem

guess I'll be pulling the pan (again) to check the length of the pump compared to the old one

I don't know about the collar but if the oil pump slot is at ninety degrees to your shaft, it won't go down. Sometimes you have to rotate the pump a bit with a screw driver.

nope that's not it. I can get it to engage the pump shaft and the cam gear but I just measured the distance on an older 53 motor that I have and this new pump is definitly 1/4 inch longer. In fact it almost touches the cam gear. I'll just pull the pan this weekend and see what I've got goin on in there. Maybe Cevy Classics sent me the wrong pump. I thought they were all the same for the 235's.

The 235 pump should be the same for passenger and truck 56-62 235s.

However, there are two different pumps that were used in pre-1955-2nd 235s.

Do you have a 1953 or a 1958 motor? The 1953 pump would be different from the 1958 pump.

I have 2 motors a 53 and a 58 the one I'm rebuilding is a 58. I have 2 distributors. one from each. Niether one will go all the way in with the new pump but both will go in on the 53 motor.the lengths on both dizzy's are the same. I wonder if the difference in the pumps is the lenth or something else. I'll find out when I take everything apart again and can compare them side by side. Both pumps are marked M45. I don't know about the one in the 53 motor cause it's mostly still together.By the way on another thread we talked about a timing issue setting the valves. I think I may have lined up the timing marks on my crank and cam gears but had the crank 180 degrees out. Now I guess I have to undo the timing cover too. I'm getting good at tearing this apart. Too bad I used lots of loctite in certain places.

nevermind on the timing issue. Just checked again and it's looks like everything is OK. I am just overthinking the situation now. I was confusing myself with which rotation the crank was on. Easy enough to tell by putting a wet paper towel in # 1 hole and cranking by hand until it blows out. the dizzy and oil pump issue will have to wait until monday when I can call Patricks.

not the same year, but i checked the bottom of my dist and there's 1/4" of the shaft that has a 'shoulder' that needs to seat into the slot of the oil pump. if it hangs up on the shoulder, the dist will be out of it's hole by 1/4"
1/4" shoulder coincidence?

OK problem solved. My fault. When I put the pump in I didn't realize it wasn't lined up right with the hole for the bolt and jam nut. I actually let it go down too far. By raising it 1/4 inch it lined up on the hole correctly and I was able to bolt it up better. Now the dizzy goes all the way in. Dumb mistake ,won't happen again. This should be the end of this thread ( unless someone want's to laugh at my mistake).thanks

i'll laugh for the both of us bec i'm pretty sure that i'm the king of not seeing what i'm not seeing

Hi. I am in the process of re-assembling my 261 after getting it back from the machine shop. I dropped in a new distributor from Tom Langdon and it appears that I have the same problem with the distributor shoulder not meeting up with the machined surface of the engine block (i.e. there is a 1/4" gap from getting the distributor fully seated). I have not putzed with it yet, but dread the thought of dropping the oil pan to see how the oil pump was installed by the machine shop. Any recommendations?

Thanks!
Dan M.

I don't know if your situation is the same or not but if it is you will have to drop the pan, loosen the retaining bolt and jam nut and then move the oil pump until the bolt and hole line up . when it is in the right position the bolt should screw almost all the way in.

did you take into account that the distributor turns with the cam teeth when your installing it. make sure that the pump shaft is turned the same amount, or have someone bump the starter while your holding the distributor and it should drop in.