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Hello.
i have a stuck "compressed" lifter for the exhaust valve on my #3 cylinder, 348 straight eight.

how hard is it to get this out?
will it come out if i take off the retaining clip or will it fall into the block?

thanks in advance, Dave in Tampa

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Though it is possible to remove one set of rocker shaft/cam follower arms and rollers (which I believe will allow dropping a lifter out from below) without removing the head, it's a job best left to someone who has done it before though I see in your picture the retaining nuts have been removed so perhaps that's in progress? Generally, to remove the lifter (from above) you will have to remove the cylinder head and then the valve spring and valve above that lifter. That said, I'm not sure just what you mean by a compressed lifter, they are mechanical and not hydraulic so they don't have a "compressed" position, it's a solid shank of steel with an adjustable length which rides at the lower end on a hardened steel pad which is located on an arm with a pivot at one end (attached to the external rocker shaft) and a roller on the other which follows the camshaft. Earlier engines had stamped arms, later had forged and they are are interchangeable. It's not possible to have a stuck lifter in the lower position unless there is damage to the camshaft, follower arm, or roller and pin. I'd suggest starting by taking a good look at the construction of the valve train from a picture in the parts manual of any of the senior engines thru 1939, and they reevaluating what you see and letting us know. It's also nearly impossible to have a lifter stuck in the "up" position.

BTW, if you have a 626/633 you have a "320" engine, if a 640/645 it's a 384.

Ok, this what happened,
i was driving down the road and car started running like crap, a bad miss and lots of noise. i had the car towed home and the first thing i did was pull the spark plugs.

all were good except number 3. that plug was wet and fouled. so i tried the spark test, very good hot spark, next i pulled the valve cover { see photo } and had my son push the starter and thats when i noticed the lifter for #3 exhaust was not pushing up on the vavle. BUT, it does go up and down, just not as much as it should compared to the other lifters.

now, i had assumed that there was a plunger and spring on the bottom of the lifter, but since i have never looked at an engine this old i guess i am wrong.

i have taken off the nuts to the follower cover but have not removed it, i figure i would try to find some photo's or someone who has done this before i get to deep into it.

i have worked on plenty of overhead valve engines from the 50's to the 80's but have never worked on a flat head so all this it new to me.

also, i believe this is a 384.

if any of you have photo's you can post or a link to photo's it would help very much. i have all the tools i need to do the job but i want to figure out exactly what i have first.

thanks, Dave

Here's a cross-sectional engine image from the 33-36 parts manual, pretty much the same for all Senior 6s and 8s from 1923 thru 1939. Can't do much to improve the image quality and I probably have a better one somewhere but I think it's quite self-explanatory as to the design of the valve train.

I suspect you've either lost a roller and pin or bent a rocker arm; damage to the cam itself is less likely unless you continued to run the engine.

It's a bit of a trickly job, but you can remove the set (for 4 cylinders) of the rocker shaft/housing and arms w/o removing the head or removing the cylinder bore casting from the crankcase. It's been perhaps 35 years since I've done this, but from memory -- you'll have to use enough valve spring compressors to elevate each spring where the camshaft lobe isn't in the down position and for those that are you may need to increase the lifter mechanical adjustment clearance and hold them up with closepins, rubber bands or similar. Then with no valve spring pressure on the rocker arms you should be able to remove the entire rocker shaft/arm assembly with judicious wiggling. I suspect you'll find a bent rocker arm or worn roller and pin. Repro rollers and pins are available from Egge and if the arm itself is bent you can probably find a replacement easily enough and if yours are the stamped steel ones (which really aren't a problem, generally) you could consider replacing them all with the later forged arms. I had quite a few of these forged arms but recently sold 24 of them to a gentleman in Norway for the same purpose - but I may have one or two left over if that's of use to you.

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That photo is perfect, thank you.

i searched and found that Kanter and a couple others have the arms with pin and roller for around $30. - 40.
this weekend i will work on getting it apart to inspect.

i just hope no damage to the cam, i was driving at around 35, 40mph when this happened.

will let you know what i find when its apart.

thanks a million, Dave

Update - i have removed the rocker assembly and found a bent arm. NO damage to the cam thank god.

i believe it is stamped steel, not forged.

i noticed there is a bushing soldered into the arm, can i assume the new ones DO NOT come with a bushing?

here are some photo's.



if anyone has some advice i would welcome the input.

the internal dia. of the bushing is .500



thanks, dave

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Thanks for the pictures. Just as I suggested to you a few posts earlier in this thread, a bent arm so you'll need a new arm, roller and pivot (Egge and others have them) and perhaps you can save the hardened pad that contacts the base of the lifter. But the real question is why did it bend? Better next check the lifter to see if it's free, and if the valve is free as well; pretty good guess is something there is what caused the problem in the first place. Yes, you've got the stamped arms, correct for that series of engines.

I doubt you'll find any NOS arms anymore but yes, the sleeve was part of it. Still it should be easy to find a used one, if no where else Kanter's has mountains of old engines and as I said earlier, if you can find the forged arms you could make a replacement but they must be done in pairs - no spring between them, just a precision fit to fill the space.

Hi Owen,

thank you very much for the help.

the lifter goes up & down just fine, and no woble.
i put my finger in the rocker opening and felt the bottom of the lifter and the ones near it, it did not feel like there was damage.

now, when this happened while driving down the road, the car had backfired when i started it. i did not mention this before because this has never happened, but from what i have seen in the past some times a backfire can cause a bent pushrod in more modern cars, could that apply here?

i have a dental mirror and will check in the spark plug hole in a day or so to see if anything is in there.

now, about the hardend pad. it looks like it is rivited or spot welded. how are they attached?


Dave

Dave, I had two stuck exhaust valves on my 1930 733 and the lifter arms below both looked like yours. The rest of my lifter arms were all loose so they were all rebuilt by Claasic and Exotic Services in Troy, MI. I have some extras if you need one but even my extras are loose and will need to be repaired. I don't think yours is repairable.
Todd

Dave, curious - was the valve over the bent arm an intake or an exhaust? You might use a valve spring compressor and compress and remove the spring on that valve and see if the valve can move freely up and down - obviously something overloaded the failed arm. Beyond that I don't think I can offer much more help. The hardened pad that contacts the lifter base was a press-fit on the forged arms, I don't know how it was attached to the stamped steel arms but Todd would know.

If you consider changing over to forged roller arms, and I don't think the stamped arms are in any way a chronic problem (I've seen bent forged arms as well), keep in mind that the oiling system was also changed; the forged arms are rifle-drilled to receive oil under pressure from the shaft to the roller pin. I believe the roller pins on the stamped arms were lubricated by drip and mist. Since my experience is with the slightly later engines, I leave you in the capable hands of those that have your vintage engines. Good luck - I anxiously await hearing what the culprit was.