[Stickman]

Finally assembled long block (454 Mk IV)) with help from a friend. Did not have a dial indicator at the time to check end play. Now that cam plug and timing cover are on, I located a dial indicator and I'm showing about .021 of end play. Dial is not completely perpendicular to lobe but I feel the reading is close. Not comfortable leaving with this much play. Do I...

• Locate a longer nylon button and trim to size with current stock timing cover ?? (Currently have the CompCam #205 button .945" length installed)
• Drop $160 on a Cloyes cover and remove the nylon button and adjust using thier roller button setup ?? Read about possible clearance trouble using the Cloyes 9-231 cover with a 8" balancer or short water pump. (rather use that cash towards other parts)
• Tack in a thin piece of metal to inside of cover and trim current nylon button to achieve .007 - .010 end play ??

I just can't see leaving this and risk damage to a new distributor gear, possible timing issues or worst case, have lifters shaving edge of lobes from too much walk...

 

[Ericnova72]

Put a small circular .010" thick shim behind the button, against the face of the cam to space your current button out the needed amount.

 

[Stickman]

Hmm.. I like the way you think. Do they actually make shims for nylon buttons , or just get some .010 shim stock and cut your own ??

 

[Jebchevelle]

Hmm.. I like the way you think. Do they actually make shims for nylon buttons , or just get some .010 shim stock and cut your own ??

just make your own.

 

[BillK]

First of all I dont really think you can get a good reading the way you are measuring it. Take the cam plug out of the back and check it there.

Take the timing cover of and smack it with a hammer ? Then fit the Teflon button.

Or weld a washer to the inside of the cover and then grind it smooth. That's what guys have done for years and it stiffens up the cover some too.

Personally I do not like the roller buttons. I have seen one in pieces in an oil pan and that was enough for me not to use them.

 

[fauxrs]

On my big block i trimmed a shim out of a soda can and put it behind my button, nailing the clearance right on the money.

 

[jeff swisher]

On my SBC the first roller cam I ever ran I took a crankshaft bolt washer Yes the front one that is very thick.
I tapped it and added a set screw to it and welded that thick washed to the front of my timing chain cover.
I could set end play by tightening the set screw.
Yes it cleared the back of the water pump.

 

[David Ray]

Another thing a lot, and myself, have done to enhance the nylon bumper with a stock steel cover is to use a longer bolt and nut to add to one of the rear cover bolts for the water pump.

Even though the stock timing cover is steel, and fairly stout, with use, the cover can distort, the bolt, or a thrust plate and button/bolt will help stop the cover from "bulging" under stress.

 

[Bob Tiley]

I was going to say to tack weld a square piece of metal to the inside of the timing cover.

 

[Stickman]

Appreciate the responses...

 

[Ericnova72]

Hmm.. I like the way you think. Do they actually make shims for nylon buttons , or just get some .010 shim stock and cut your own ??

Cut your own is probably easiest, especially if there is a time crunch.

If you want to buy, McMaster-Carr Industrial Supply....ring shims. About $8-10 for a pack of 10 pcs.

 

[Stickman]

OK.. as Bill mentioned, I was not getting an accurate reading previously. So... how can I measure without removing the cam plug ?? Cam plug is installed and now inaccesible in engine stand. Came up with a plan. Take wooden clothes pin, notch opening square with dremel, fit over lobe. Now I can place the pointer perpendicular to patent pending "lobe measurement extender device". Measurement is now .018 instead of .021. Appears angle of dial pointer increases reading. So I'm stil looking at putting a .010 shim behind button. That should hopefully keep me within the .007 - .010 range with a little cover deflection.

 

[David Ray]

I read above about "tack welding" a metal square INSIDE the timing cover, NOT ADVISED.
Yes on the metal square on the timing cover, BUT, ON THE OUTSIDE OF IT. Possibly, a really BAD deal if a tack welded part comes loose inside the timing cover, or anywhere else inside the engine.

 

[BillK]

OK.. as Bill mentioned, I was not getting an accurate reading previously. So... how can I measure without removing the cam plug ?? Cam plug is installed and now inaccesible in engine stand. Came up with a plan. Take wooden clothes pin, notch opening square with dremel, fit over lobe. Now I can place the pointer perpendicular to patent pending "lobe measurement extender device". Measurement is now .018 instead of .021. Appears angle of dial pointer increases reading. So I'm stil looking at putting a .010 shim behind button. That should hopefully keep me within the .007 - .010 range with a little cover deflection.

I would have to bet that you are getting some deflection on the clothes pin unless you have an indicator with a VERY light spring. To be honest with you I would leave it alone.

 

[Stickman]

I read above about "tack welding" a metal square INSIDE the timing cover, NOT ADVISED.
Yes on the metal square on the timing cover, BUT, ON THE OUTSIDE OF IT. Possibly, a really BAD deal if a tack welded part comes loose inside the timing cover, or anywhere else inside the engine.

Agreed... I'm opting to not tack anything on the inside of the cover for that reason

I would have to bet that you are getting some deflection on the clothes pin unless you have an indicator with a VERY light spring. To be honest with you I would leave it alone.

The dial is very light and there is no movement of wood. I have re-measured a dozen times and get the same reading. I don't want to leave this since it's 2x the recomended amount of play. Should be easy to adjust with a shim behind the button.

 

[427L88]

repeatability is the key. Nice "mcgiver' setup.

 

[Stickman]

repeatability is the key. Nice "mcgiver' setup.

...Imagination is more important than knowledge

 

[BillyGman]

On my SBC the first roller cam I ever ran I took a crankshaft bolt washer Yes the front one that is very thick.
I tapped it and added a set screw to it and welded that thick washed to the front of my timing chain cover.
I could set end play by tightening the set screw.
Yes it cleared the back of the water pump.

FWIW to the OP, Cloyes makes a timing cover like that with the set screw in the middle. And per their instructions, they want you to just snug it down, and their claim is that since the cover is aluminum, when the engine gets to full operating temp, the cover and it's set screw will expand and have about the right amount of cam end play automatically

 

[BillyGman]

This is the timing cover with the adjustable "quick button" for the cam end play. You just snug it down and when the engine warms up, you automatically have your correct end play so you don't have to screw around with shaving a cam button.....

Cloyes Gear 9-231 Cloyes Quick Button Two-Piece Timing Covers | Summit Racing

 

[Stickman]

This is the timing cover with the adjustable "quick button" for the cam end play. You just snug it down and when the engine warms up, you automatically have your correct end play so you don't have to screw around with shaving a cam button.....

Cloyes Gear 9-231 Cloyes Quick Button Two-Piece Timing Covers | Summit Racing

Thanks for the link. I did look into that cover, but after reading the instruction manual there are a couple concerns. I do have an 8" balancer and after market Stewart waterpump. So there may likely be fitment issues. ..and $170 could be used elsewhere. I already have a "plan" and will update thread if successful...

WARNING! This timing cover has been designed to fit behind the Chevrolet short water pump. However, some aftermarket racing pumps may not provide adequate clearance. If the water pump does not provide clearance, the Quick Button® cam thrust button may be overloaded. Check for clearance using feeler gauges or paper. It may be necessary to modify the cover, water pump, or both.
WARNING! This timing cover has been designed to accommodate up to a 7-1/2" vibration damper. Some larger dampers, such as the Chevrolet 8" replacement, may interfere with the Adapter Plate screw heads.