The thing to remember is that when the engine cam gear is driving the oil pump gear the thrust created by the gear geometry is downward forcing the distributor gear thrust surface against the block thrust surface. The torque required to drive the pump is quite high at all times even at idle. This means the distributor gear is never going to float off the block thrust surface while running.
High volume and high pressure oil pumps oil pumps tend to accelerate gear wear, as the higher torque across the helical gear increases the thrust / axial load. Another thing I got involved with back in the late -70’s was distributor gear backlash, and had made up dummy distributors to measure. Excessive backlash would lead to spark / timing scatter.
George have heard the wear factor before. But not bad at 20 years of use. Can’t see how all the play I had did not have any issues that I know of. Maybe it did ?
Tim Tim why is it giving me the guidelines to comment on your channel and then not letting me come in if you received this I received or sent hundreds of things to you it seems like and never been disrespectful @@DragBoss351Cleveland
@@DragBoss351Clevelandalso if you get a chance can you let me know if you helped Andy at Unity Motorsports on his distributor or tried to figure out what his problem is can you assist him on that maybe
The conditions to check are that the bottom of the gear contacts the thrust surface in the block when dizzy is installed and that the dizzy shaft is raised slightly when clamped in place and that when clamped in place you can further lift the shaft slightly, creating a clearance between the gear thrust surface and block thrust surface. These checks ensure that that the gear rides freely on the block thrust surface and you don’t bind the dizzy shaft when clamped in place. I don’t have exact numbers off top of my brain but if for example you had .020 total float in the dizzy uninstalled, you could look for say .010 after installation. The blocks are very old and they vary with respect to the distance between the block thrust surface and the surface the dizzy clamps up on. Not sure one can simply trust the specs that are floating around out there.
I believe the torque from the oil pump pulls the gear "down " alllll the time ,and is tight against the block, your measuring something that dosen't matter..that shaft will never go up on a running engine. I do watch and LIKE your channel..
The conditions to check are that the bottom of the gear contacts the thrust surface in the block when dizzy is installed and that the dizzy shaft is raised slightly when clamped in place and that when clamped in place you can further lift the shaft slightly, creating a clearance between the gear thrust surface and block thrust surface. These checks ensure that that the gear rides freely on the block thrust surface and you don’t bind the dizzy shaft when clamped in place. I don’t have exact numbers off top of my brain but if for example you had .020 total float in the dizzy uninstalled, you could look for say .010 after installation. The blocks are very old and they vary with respect to the distance between the block thrust surface and the surface the dizzy clamps up on. Not sure one can simply trust the specs that are floating around out there.
I got lucky and bought the GM shims that went between the gear and the housing on a HEI distributor before they quit making them. But still needed to set the height of the distributor to oil pump. engagement.
With a crank trigger the wear or even out of spec does not affect timing ° ; however check rotor phasing . Btw , chamfer the oil grooves on the back of the cam sprocket . Especially the Cloyes .
excellent explanation, I used my 351w dist. in my Cleveland same distributor shaft length, and oil pump drive, just different gear. I even used the same drift pin hole and location was in spec. Ford and MSD have different specs, one may be end play in, and one out, don't recall just now. I used Ford spec for Mallory dist. I was really surprised you got 20 years out of that bronze gear, that baby was dialed in. I use melinite gears when I don't know what the cam material is. the 8 to 10 thou clearance looks much better, and I'm glad you stated when dist. is bolted down. My machinist told me 20 years ago the camshaft gear and the dizzy gear have to float ever so slightly for alignment to account for hard acceleration and deceleration, makes sense to me. I suppose a guy could use a thicker distributor gasket if clearance is too tight, just for a get by. You tube guys having this issue right now are Andy on Mixed Up Boss and the Running Rust guys, hope they watch this and figure it out.
Easy question - do distributors that don't run points like your MSD still wear out? By wear out I am referring to space growing between the distributor shaft and the distributor housing. Yes, I know that is not a Cleveland motor question. Am asking as years ago I ran points and high spring tension points caused that distributor to wear out over 60k miles. Am asking as the non points distributor that I put 40k miles ago on my mostly stock 351c has never been checked for wear. I just occasionally check the cap and rotor for wear.
Tim, ditch the bronze gears.... They wear quickly, even on low-time scenarios such as what you have. Billet steel cams get steel gears. I haven't used a bronze gear in 17 years. Never have had a wear issue when installed correctly.
Drift to get the roll pin out. Small steel disc at the bottom of the dist. shaft and a small puller to get the gear off.(This keeps from damaging the shaft and the take-off gear.) Hold the shaft in a soft jaw vice. A long socket of the proper i.d. will work fine for replacement gear installation. Installed dist. gear height is critical for proper full mesh with cam gear. I check this with every new cam and dist. gear. And always use chromemoly oil pump drive. NEVER the O.E.-style pencil drive... EVEN if using lighter oils and a non H.V or H.P. pump.
The thing to remember is that when the engine cam gear is driving the oil pump gear the thrust created by the gear geometry is downward forcing the distributor gear thrust surface against the block thrust surface. The torque required to drive the pump is quite high at all times even at idle. This means the distributor gear is never going to float off the block thrust surface while running.
Applicable to 460's too , admire the attention to detail . Car Craft once called it " Looking for the Demon Tweak" .
High volume and high pressure oil pumps oil pumps tend to accelerate gear wear, as the higher torque across the helical gear increases the thrust / axial load. Another thing I got involved with back in the late -70’s was distributor gear backlash, and had made up dummy distributors to measure. Excessive backlash would lead to spark / timing scatter.
George have heard the wear factor before. But not bad at 20 years of use. Can’t see how all the play I had did not have any issues that I know of. Maybe it did ?
Tim Tim why is it giving me the guidelines to comment on your channel and then not letting me come in if you received this I received or sent hundreds of things to you it seems like and never been disrespectful @@DragBoss351Cleveland
@@DragBoss351Clevelandalso if you get a chance can you let me know if you helped Andy at Unity Motorsports on his distributor or tried to figure out what his problem is can you assist him on that maybe
the man the myth the legend. The Drag boss
I love it, I wish. If I work hard maybe one day. I did go to Rual King yesterday and guy came up to meet me. 😊 I’m trying
The conditions to check are that the bottom of the gear contacts the thrust surface in the block when dizzy is installed and that the dizzy shaft is raised slightly when clamped in place and that when clamped in place you can further lift the shaft slightly, creating a clearance between the gear thrust surface and block thrust surface. These checks ensure that that the gear rides freely on the block thrust surface and you don’t bind the dizzy shaft when clamped in place. I don’t have exact numbers off top of my brain but if for example you had .020 total float in the dizzy uninstalled, you could look for say .010 after installation. The blocks are very old and they vary with respect to the distance between the block thrust surface and the surface the dizzy clamps up on. Not sure one can simply trust the specs that are floating around out there.
Thanks Tim. Alot of people don't check it on any type of engine.
I believe the torque from the oil pump pulls the gear "down "
alllll the time ,and is tight against the block, your measuring something that dosen't matter..that shaft will never go up on a running engine. I do watch and LIKE your channel..
I would think that it would too, but had so much clearance, I figure hey might as well change it. Thanks for watching, more on the way. 🏁🇺🇸
The conditions to check are that the bottom of the gear contacts the thrust surface in the block when dizzy is installed and that the dizzy shaft is raised slightly when clamped in place and that when clamped in place you can further lift the shaft slightly, creating a clearance between the gear thrust surface and block thrust surface. These checks ensure that that the gear rides freely on the block thrust surface and you don’t bind the dizzy shaft when clamped in place. I don’t have exact numbers off top of my brain but if for example you had .020 total float in the dizzy uninstalled, you could look for say .010 after installation. The blocks are very old and they vary with respect to the distance between the block thrust surface and the surface the dizzy clamps up on. Not sure one can simply trust the specs that are floating around out there.
Great work Tim Keeping the clevo singing..🦾
I got lucky and bought the GM shims that went between the gear and the housing on a HEI distributor before they quit making them. But still needed to set the height of the distributor to oil pump. engagement.
With a crank trigger the wear or even out of spec does not affect timing ° ; however check rotor phasing . Btw , chamfer the oil grooves on the back of the cam sprocket . Especially the Cloyes .
excellent explanation, I used my 351w dist. in my Cleveland same distributor shaft length, and oil pump drive, just different gear. I even used the same drift pin hole and location was in spec. Ford and MSD have different specs, one may be end play in, and one out, don't recall just now. I used Ford spec for Mallory dist. I was really surprised you got 20 years out of that bronze gear, that baby was dialed in. I use melinite gears when I don't know what the cam material is. the 8 to 10 thou clearance looks much better, and I'm glad you stated when dist. is bolted down. My machinist told me 20 years ago the camshaft gear and the dizzy gear have to float ever so slightly for alignment to account for hard acceleration and deceleration, makes sense to me. I suppose a guy could use a thicker distributor gasket if clearance is too tight, just for a get by. You tube guys having this issue right now are Andy on Mixed Up Boss and the Running Rust guys, hope they watch this and figure it out.
I would be inclined to put a shim in between the gear and the body so it cannot drive the shaft up on rotation .
Easy question - do distributors that don't run points like your MSD still wear out? By wear out I am referring to space growing between the distributor shaft and the distributor housing. Yes, I know that is not a Cleveland motor question. Am asking as years ago I ran points and high spring tension points caused that distributor to wear out over 60k miles. Am asking as the non points distributor that I put 40k miles ago on my mostly stock 351c has never been checked for wear. I just occasionally check the cap and rotor for wear.
Dont forget by the time oil goes through it itll be even a leser end float
Tim, ditch the bronze gears.... They wear quickly, even on low-time scenarios such as what you have. Billet steel cams get steel gears. I haven't used a bronze gear in 17 years. Never have had a wear issue when installed correctly.
What’s funny Brent is I have not changed this in 20 years and never an issue. The other new distributor, going to do that with. Thanks for watching
How do you know where to drill ?
Measure vertically ? With gear on shaft ...
Does the hole go where the old one was ?
I’m thinking I saw you using a hammer to press the gear off and on ??? Hmm.
Used a center punch and my 40 year old hammer 🔨 Bruce
Drift to get the roll pin out. Small steel disc at the bottom of the dist. shaft and a small puller to get the gear off.(This keeps from damaging the shaft and the take-off gear.) Hold the shaft in a soft jaw vice. A long socket of the proper i.d. will work fine for replacement gear installation. Installed dist. gear height is critical for proper full mesh with cam gear. I check this with every new cam and dist. gear. And always use chromemoly oil pump drive. NEVER the O.E.-style pencil drive... EVEN if using lighter oils and a non H.V or H.P. pump.