Posted By: 65rbdodge
exhaust valve rotaters - 04/01/11 07:18 PM
what is their purpose? do i need them? they are on #302 heads on a near stock 318.
exhaust valve rotaters
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/01/11 07:43 PM
They use a very short valve spring and any added lift would be very marginal before coil bind. Get rid of them and use regular retainers and regular length springs if upgrading to bigger cam..
They are to help prevent valve and valve seat burnouts by keeping the valve in constant rotation in the guide allowing a different seating position each time the valve closes.
They are to help prevent valve and valve seat burnouts by keeping the valve in constant rotation in the guide allowing a different seating position each time the valve closes.
Posted By: pishta
Re: exhaust valve rotaters - 04/01/11 07:48 PM
Mostly used in trucks and industrial motors, as said, they help in preventing buildup on the exhaust valve face. They are physically heavier than normal retainers so they are usually tossed in a performance rebuild. On a stock motor, they hurt nothing.
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/02/11 01:04 AM
ditch thoise and use a diff spring with 8 more stock intake retainers
PM if you need 8 more retainers,I have a bunch you can have
PM if you need 8 more retainers,I have a bunch you can have
Posted By: NITROUSN
Re: exhaust valve rotaters - 04/02/11 02:55 AM
Quote:
They use a very short valve spring and any added lift would be very marginal before coil bind. Get rid of them and use regular retainers and regular length springs if upgrading to bigger cam..
They are to help prevent valve and valve seat burnouts by keeping the valve in constant rotation in the guide allowing a different seating position each time the valve closes.
Well said...
Most readers will say throw it away not knowing that they do work and have reason to be there on certain applications.
Posted By: dOc !
Re: exhaust valve rotaters - 04/02/11 03:14 AM
They are a VERY valuable piece on a grunt motor .. like an RV, towing or truck-type motor. Very TRUE ... they are not a high-rpm HP part at all.
I have no OEM cost-diff ... but I would wager that those retainers cost Ma Mopar 4 TIMES what a standard piece costs.
DON'T throw-em-out ...save 'em furr me !
I have no OEM cost-diff ... but I would wager that those retainers cost Ma Mopar 4 TIMES what a standard piece costs.
DON'T throw-em-out ...save 'em furr me !
Posted By: dOc !
Re: exhaust valve rotaters - 04/02/11 10:04 PM
AFTER thinking about this post I had to go out to the barn and pull a rotator off a set of heads.....
DAMN that thing is trick ... there is some kind of "bearing" in there ....roller or ball.
DAMN that thing is trick ... there is some kind of "bearing" in there ....roller or ball.
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/02/11 11:56 PM
Quote:Here in picture form. Not all were on truck engines many were on cars too. Did you notice how short the springs use with them are.
AFTER thinking about this post I had to go out to the barn and pull a rotator off a set of heads.....
DAMN that thing is trick ... there is some kind of "bearing" in there ....roller or ball.
Posted By: dOc !
Re: exhaust valve rotaters - 04/03/11 01:49 AM
It appears to me that the keepers go deeper into the retainer itself ... diff height springs ? ... The one I have here is about 2.200.
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/03/11 01:53 AM
Very much different height springs. If your's aren't someone has really compressed them to get them in. I can get some virgin springs tomorrow set up and picture.
Posted By: dOc !
Re: exhaust valve rotaters - 04/03/11 02:02 AM
I went out and found a well-used) HP spring(with the dampner) .. it appears to be the same height. definately wider though.
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/03/11 02:08 AM
Well I also went out an looked and mine went out last fall clean up. I am sure that the ones I have had off over the tears were shorter to compensate for the thick retainer. I may mistaken as it has been a while and I won't argue with you. Life is too short. I do know that when this came in the shops here the whole thing was swapped out. I have a dam good memory but it is getting shorter all the time and it never was too long. I would still use spring compatible with the cam.
Posted By: NITROUSN
Re: exhaust valve rotaters - 04/03/11 03:04 AM
Quote:
I went out and found a well-used) HP spring(with the dampner) .. it appears to be the same height. definately wider though.
This is where the problem comes in. Intake springs will fit just fine but look out. You have to be very carefull and loaded spring rates should be checked.
Years back we had a shop do a valve job on a 79 318 power wagon. Within 60 miles it was towed back with a dropped exhaust valve. The heads were pulled and sent to a rebuilder for a un-biased opinion. Result was intake springs accidently installed on exhaust valves with rotators. The seat pressures were like doubled if not more as I remember.
Not sure on the physical heights between them.
Posted By: dOc !
Re: exhaust valve rotaters - 04/03/11 03:26 AM
Quote:
I am sure that the ones I have had off over the tears were shorter to compensate for the thick retainer.
...and I should make it very plain .. the springs I have here are certainly used. And those rotating retainers ARE much thicker .. but again ...it APPEARS that the keepers sit waaaay lower into the retainer itself.
Now I can NOT compare a "std" retainer on the exh valve because the stem size on the 1.50 exh valve is so much larger.
A side note ....I put the rotator on the HP spring ...and it fits fine.
Posted By: dOc !
Re: exhaust valve rotaters - 04/03/11 03:32 AM
Quote:
dropped exhaust valve. The heads were pulled and sent to a rebuilder for a un-biased opinion. Result was intake springs accidently installed on exhaust valves with rotators. The seat pressures were like doubled if not more as I remember.
Not sure on the physical heights between them.
So it BROKE the stem of the valve ? ...
I am going to have some EXTENSIVE work(DEporting and swirl work) done to these heads and I will be sure to have the cyl head guy check all open and closed pressures.
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/03/11 11:52 AM
Something is not right there, doc. We ave always used standard retainers on the valve when changing springs. Here is a picture of a result of using rotators with a small 485 lift cam. As there had been new valve installed on the job the good ones were reused on nondamaged heads. Have used standard retainers and compatible springs on many since.
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/03/11 06:13 PM
a stock exhast spring with rotator is shorter than the stock intake spring
I had a machine shop mix one intake spring up on a valve job
couple days later it snaped the end off the valve,locks and tip of valve still in the rotator when I tore it back down
busted a piston,wiped the cyl walls out,suck piston into almost all other cyls
I told and showed them the 8 shorter springs and the bigger intake springs when I droped them off for the valve job
I will never use any more rotators when a rebuild or spring upgrade is at hand on mine
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 08:05 AM
Quote:
Something is not right there, doc. We ave always used standard retainers on the valve when changing springs. Here is a picture of a result of using rotators with a small 485 lift cam. As there had been new valve installed on the job the good ones were reused on nondamaged heads. Have used standard retainers and compatible springs on many since.
Don ....NOT RIGHT ? ... I am a newbie at this. NEVER tried any type of R&D on these type heads ever before. I am learning as I am going-along.
That damage ...
....what are you suggesting that the rotators did to cause that ?
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 08:18 AM
Quote:
a stock exhast spring with rotator is shorter than the stock intake spring
I had a machine shop mix one intake spring up on a valve job
couple days later it snaped the end off the valve,locks and tip of valve still in the rotator when I tore it back down
busted a piston,wiped the cyl walls out,suck piston into almost all other cyls
I told and showed them the 8 shorter springs and the bigger intake springs when I droped them off for the valve job
I will never use any more rotators when a rebuild or spring upgrade is at hand on mine
Mike ....I have to ask you the same Q .... wassssupy ? ...
These are feeble low-lift cams... no chance of over-taxing the springs or coil-bind....
I have both of the spring in front of me ... the 413 exh VS(really a feeble looking piece) ...and then the HP spring with the dampner. Same height, same ID .... the rotators sits FINE in the HP spring .....
I like the idea of using the HP spring....to have more pressure on the cam to insure good contact and-TO INSURE good lifter movement ...PLUS with the inner dampner .. it prevent excess oil getting into the valve guides.
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/04/11 11:05 AM
Doc,I can only speak of the ones I have messed with and they are on SB
I have never checked a set on a BB
I have never checked a set on a BB
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/04/11 12:16 PM
Just go along with him, Mike. Life is easier that way. we know that they are short but ------------
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/04/11 01:12 PM
---------
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 04:52 PM
Quote:
Just go along with him, Mike. Life is easier that way. we know that they are short but ------------
Hey you
..... wasssupy ? .. 
Are BOTH of youz guyz talkin' 'bout small-blocks ? ... I have had no experience at all with them ... but I do have a guy digging-me-up a couple of early 70's 360 core-motors.
Just GO ALONG with me ? .. on most topics ... TRUE 'dat ! ... but I am the one ASKING here ....not telling.
You say they are "short" ? ... how much shorter? I will pull an intake VS off the 413 shortly and get the spec.
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/04/11 05:59 PM
By the way DF. the original post was on Small blocks. Mike and I have been answering for small blocks to the OP. You step in and muddy the water with your posts without telling anyone that you are talking BB till after the fact. By the way Mopar valves are 3/8 stemmed unless oversize stems or stelite valve may have a heavier stem. Don't remember for sure and it has been a long time since I have seen either a HD BB with rotators or stelite valves. Probably close to 30 years or more. Like said I have a good memory but slightly shorter than that. You want to change the subject start your own. 
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 06:15 PM
M4L .... 
at choo !
Exh valve rotators ? ....SB ...BB ... whatever !! ....start my own topic ? ... oh THAT should be a hot-topic !!
Justa FYI ... the 413 exh valve has a HUGE stem. Ever hear of a sodium-filled valve ?
How many RV motors have you pulled-down? LOTS of issues on the exh-valve side?
at choo ! Exh valve rotators ? ....SB ...BB ... whatever !! ....start my own topic ? ... oh THAT should be a hot-topic !!
Justa FYI ... the 413 exh valve has a HUGE stem. Ever hear of a sodium-filled valve ?
How many RV motors have you pulled-down? LOTS of issues on the exh-valve side?
Posted By: MoparforLife
Re: exhaust valve rotaters - 04/04/11 06:26 PM
Quote:Yeah I have heard and seen them again I said it has been awhile. They are relative and about the same as a stelite valve have larger stems. I also said it has been a while since I was around them and can pick and chose what I want to work on, if anything. I quit the dealerships in 82 so go figure. This wasn't talking HD truck or RV motors wither. So go muddy somebody elses threads or preferably start your own thread rather than horn and ruin on someone elses. I am outta this one.
M4L ....
Exh valve rotators ? ....SB ...BB ... whatever !! ....start my own topic ? ... oh THAT should be a hot-topic !!
Justa FYI ... the 413 exh valve has a HUGE stem. Ever hear of a sodium-filled valve ?
How many RV motors have you pulled-down? LOTS of issues on the exh-valve side?
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 06:32 PM
RUIN this thread ? ... I reject that
The OP's question was answered and I simply asked a Q or two and started a little chat that was directly ON TOPIC of an ..
...exhaust valve rotater.
The OP's question was answered and I simply asked a Q or two and started a little chat that was directly ON TOPIC of an ..
...exhaust valve rotater.
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/04/11 09:00 PM
my 360 headed 318 has sodium filled exhast valves and had the rotators on them with a shorter spring than the intake valve did..again SB
after seeing the pic that Don posted of a droped valve,then haveing my 2500$ short block trashed by a droped valve 2nd day on the road...then me finding the tip and locks still in the rotator and 1 spring bouncing around in the VC that was a tall intake spring
and I pointed that out when I droped it at the machine shop too!!!!
I double check them myself from now on..live and learn
after seeing the pic that Don posted of a droped valve,then haveing my 2500$ short block trashed by a droped valve 2nd day on the road...then me finding the tip and locks still in the rotator and 1 spring bouncing around in the VC that was a tall intake spring
and I pointed that out when I droped it at the machine shop too!!!!
I double check them myself from now on..live and learn
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 10:05 PM
So if the tip of the valve stem and the locks were still in the retainer .... how is that the fault of the rotating retainer ?
If one of the springs were shorter(as suggested above) ... would that then possibly kick-out the locks and then drop the valve that way ?
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/04/11 10:36 PM
the spring was an intake spring..which is taller
it was compressed to much at the installed hieght,pressure was incressed cause of that
lift was reduced for the retainer and valve guide clearance and made the spring coil bind with the .485 lift
i am sure there was more to it than that but the fact was I found the wrong spring had been installed on it
but the valve guide and seal was chewed up,tip broke off valve,piston shatterd,cyl bore gouged up by piston pin..ect..
dont think a piston hitting a valve will snap the end off of it and leave the locks on the tip in the retainer
the valve that was broke was in the oil pan bent to a 90*
machine shop was good for it and agreed that it was the taller spring snaped the valve tip off then the valve then fell down the hole after the piston shatterd
it was compressed to much at the installed hieght,pressure was incressed cause of that
lift was reduced for the retainer and valve guide clearance and made the spring coil bind with the .485 lift
i am sure there was more to it than that but the fact was I found the wrong spring had been installed on it
but the valve guide and seal was chewed up,tip broke off valve,piston shatterd,cyl bore gouged up by piston pin..ect..
dont think a piston hitting a valve will snap the end off of it and leave the locks on the tip in the retainer
the valve that was broke was in the oil pan bent to a 90*
machine shop was good for it and agreed that it was the taller spring snaped the valve tip off then the valve then fell down the hole after the piston shatterd
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 10:45 PM
What IS the height diff ? ... and of course ...as I mentioned above ... coil-bind can be a really bad-deal.
I am going to pop-off one of the intake springs on a 413 head and check me-self.
I am going to pop-off one of the intake springs on a 413 head and check me-self.
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/04/11 10:56 PM
eyeballing it on the bench it was a good 1/8-1/4 inch..enuff you caold see it with all 16 springs lined up 8 in a row
the one intake spring was not as tall as the other 7 when they were set back on the bench either
still taller than the 8 exhast springs but a tad shorter than the other 7 intake springs afterwords
now the comp 901-16 single with damper fit with stock seals/retainers and have room left over with a .485 lift
this was on a set of the closed chamber swirl port #302 heads also
I used 1.88/1.60 360 valves in them with a home pocket port and bowl clean up
machine shop said the spring load and coil bind was it,took the hit and redid a set of heads,machined a new block up..I had to buy 8 new pistons
never been back there either
the one intake spring was not as tall as the other 7 when they were set back on the bench either
still taller than the 8 exhast springs but a tad shorter than the other 7 intake springs afterwords
now the comp 901-16 single with damper fit with stock seals/retainers and have room left over with a .485 lift
this was on a set of the closed chamber swirl port #302 heads also
I used 1.88/1.60 360 valves in them with a home pocket port and bowl clean up
machine shop said the spring load and coil bind was it,took the hit and redid a set of heads,machined a new block up..I had to buy 8 new pistons
never been back there either
Posted By: scratchnfotraction
Re: exhaust valve rotaters - 04/04/11 10:59 PM
SB compaired to a BB is like apples and oranges...no?
I would agree that for the intended use on a stock spec engine they are worth while for longevity
but stock specs are kinda wimpy on cam lift/spring rates
I would agree that for the intended use on a stock spec engine they are worth while for longevity
but stock specs are kinda wimpy on cam lift/spring rates
Posted By: dOc !
Re: exhaust valve rotaters - 04/04/11 11:21 PM
BB to SB springs ? .. they are diff .. but I don't know in what way.
I have the height specs .... 413 IN and EXH ... 2.255 ... 2.110. HP 440 mag ... 2.105.
I have the height specs .... 413 IN and EXH ... 2.255 ... 2.110. HP 440 mag ... 2.105.
Posted By: NITROUSN
Re: exhaust valve rotaters - 04/05/11 02:46 AM
Here are some specs from the 1984 truck fsm.
318 - 360 w/o rotators took the same spring.
marked with a blue stripe 2 inches tall, .192 wire diameter, 6.4 coils installed height 1 5/8 to 1 11/16
318 w exhaust rotators marked with a white stripe 1.81 inches tall .185 wire diameter, 5.8 coils installed height 1 29/64 to 1 33/64
360 w exhaust rotators marked with a yellow stripe 1.81 inches tall, .192 wire diameter, 5.6 coils, installed height 1 29/64 to 1 33/64
All measured seat to retainer.
318 - 360 w/o rotators took the same spring.
marked with a blue stripe 2 inches tall, .192 wire diameter, 6.4 coils installed height 1 5/8 to 1 11/16
318 w exhaust rotators marked with a white stripe 1.81 inches tall .185 wire diameter, 5.8 coils installed height 1 29/64 to 1 33/64
360 w exhaust rotators marked with a yellow stripe 1.81 inches tall, .192 wire diameter, 5.6 coils, installed height 1 29/64 to 1 33/64
All measured seat to retainer.