261 Cam & Lifters

Jakeb · Member

261 Cam & Lifters

oshawacliff · Poncho Master!

Welcome back!

DonSSDD · Canadian Poncho Superstar!

how much have you been driving it, if not much regular driving, a bunch of highway driving may help settle things down?

I'd be tempted to try synthetic oil for say 500 miles or so, it will clean out things. Does your 261 have an oil filter?

Taylor55 · Poncho Master!

You have a single lifter that is getting some air trapped in it causing the lifter noise. There is a cure by drilling a small bleed hole in the lifter. If the car runs good and has a lot of power I would just run straight 30 oil with a can of general motors EOS additive. My 55 261 has the same noise on occasion and I just let it idle until the lifter bleeds down and gets the air out. If the engine is low on oil it seems to happen more frequently. Google 235/ 261 lifter repair. The person who wrote the article shows drilling the hole in new lifters before installation as the lifter noise occurs even with new lifters.

Al

Jakeb · Member

Thanks for your replies. I have been driving at least once a week. Did a long drive (4 hours one way) and back. The lifter would act up highway driving about 65 MPH. When stopped and started back up it would settle down (like Taylor55) and no issue for a long time. I just started using CAM Oil 15W40 made for flat tappet engines. Adjusted lifters one more time with car running and hot. Will see what happens from now on. I have read the articles on lifter repair and push rod mods. All makes sense, may try that if necessary. I do not have the oil filter installed. There are aftermarket lifters that have a hole in the top of the push rod seat. According to articles if you have lifters with the hole, you cut a grove into the push rod and that will allow for the air to escape.

Jake

toolnut · Member

Jaceb: Welcome to Manitoba. I obtained cam & lifters from Langdon's Stovebolt Utica Michigan <www.langdonstovebolt.com>. If you decide to do a complete rebuild contact me a 204 757 2916 with respect to converting your oil filter system to full flow.

Gary @ Lockport

long stroke · Canadian Poncho Superstar!

Jake, were those cam and lifters a hydro unit or a solid lifter unit. I had no luck finding a hydro set up that was new. I had to buy a new solid lifter set up for my 261 six in liner. I hate having to reset the lash on the cam in my 57 and i do really miss zero valve lash on the hydro unit.

Jakeb · Member

Hi all. My set up is hydraulic cam and lifters. It is a full flow system (1960). I do not use a oil filter. This winter I changed all the lifters to ones with the hole in the plunger and cut a notch in all the push rods to allow for them to bleed. Did an initial adjustment, started it and adjusted again. Took it on a drive to get the engine hot and adjusted one more time while running I have had it out on several occasions and all is well, no lifter noise, runs great. Lifters are Melling JB-761 from Rock Auto.

jmont64 · Canadian Poncho Superstar!

Good to hear when you get those results.

long stroke · Canadian Poncho Superstar!

Jake, i just want to make sure i understood you right. You replaced all your hydro lifters with new ones and you kept the cam that was already in your engine. As a general rule, cam and lifters have to be replaced as a unit because those old lobes on that cam may damage the surface on those new lifters. I hope everything is ok with your installation and i would like to highly recommend that you put ZINC additive in your oil because flat tappet cams and lifters need it in a very big way to maximize the life of both. Good luck.

Jakeb · Member

Long Stroke, I did not change the camshaft. I do use CAM oil. It has ZDDP. So far so good.

CdnGMfan · Canadian Poncho Superstar!

I remember a friend's 1957 Pontiac Pathfinder Deluxe with 261 ran so quietly that you could literally sneak up and bump someone on the back of the legs (no lifter noise at all). My modern 250 runs as quietly.

So the 261 Pontiac is the Chevy truck six but with hydraulic lifters? Is that an accurate statement?

Taylor55 · Poncho Master!

Yes that is what a 261 is. The hydraulic camshaft is referred to by GM as a high lift camshaft with lift and duration close to the camshaft used in 53-54 corvette 235 six cylinder. Even though my 261 has over 103,000 miles is still runs quiet except on occasion when one lifter bleeds down. It only happens on start up when hot after a long run and I just pull over and let it idle until it stops which only takes a minute.

Al

CdnGMfan · Canadian Poncho Superstar!

So the Pontiac 261 has a Corvette cam. Put that in any ad and watch the gearheads salivate wink

long stroke · Canadian Poncho Superstar!

Needless to say that i love those engines. Now that my 57 261 has solid cam and lifters, it is more true to the Chevrolet truck 261.