well i am finaly driving my 55 1st 3100, i passed MOT without any problems.
Now i am breaking in the engine, it has run only stationary a couple of times the last year.
It is a 261 with a 848 head and a M4F cam, rochester 1bbl and stock ignition.
in the begining the engine did run fine but the last couple of weeks every time i go for a spin it has very noisy valves and runs like crap when i come back.
i adjusted the valves a couple of times at 14/16 and this seems to work for a couple of miles.
i also noticed that it seems to occur only with a few valves around the middle of the head.
it seems that the adjuster on exhaustvalve 2 is turned in 3-4 rounds more than the others.
I did use the old valve train and i have hardned valve seats installed.
i do not want to take the head of yet if it is not nessesery. So if ther is anyone with good advice Please Help !!

Thanks,

Dennis.

Cam lobes going flat?

Dear Dennis;

It's not likely a lobe is 'going flat', but this happens.

Check the bolts that hold the rocker assembly to the head. Perhaps one or more has come loose/or was never tight.

Now; After you've made all your adjustment(s) (running), stop engine & tighten the lock nuts W/O moving the Adj. screw. Then re-check.

Also; .014 & .016 are going to be noisy if all is working right, so 'not to worry'.

The #2 Ex. might have a shorter pushrod or a bent one. If that (loose adj) 'keeps up' on that valve, (then)you may have a bad cam.

Good luck.

John and Hank,
You were both right about the cam.
it seems that there is one lobe that is going flat and is eating up the lifter in the proces.
the lifter ia already 4 mm shorter than the rest
i couldnt even get it out easy.
so i took of the front end and took out the cam
there are 3 lobes with some wear those lifters also have a diffrent wear pattern.
i always had enough oil pressure so that could not be the cause. It a new M4F cam ant new lifters that i bought from Patrick's about 1 1/2 year ago. I still want to figure out how a new cam can go flat after 200 miles.
I am going to order a new can and lifters tomorrow.

Dennis.

D;

I'm sure they will do the right thing for you.

Now would be a good time to go to the F-290 which is the upgrade for the 261 engine.

Good luck.

John,

Should that not be the F-298
and what would that do to the performance?
i would like it to run nice at 500-700 rpm.
i have the stock manifold on maybe in the future i will put on Fentons and a dual intake but not now.

Dennis.

Read this Comp Cam news flash. http://www.compcams.com/information/whatsnew/NewsDetails.asp?ListHistoryID=1985582846

If it would have something to do with the oil i am using than i would suspect the other lobes to have the same amount of wear.
I am using 15w40 and when hot i get a oilpressure of 25-30 at idle.
As i said ther are 3 lobes with wear sign and the 2nd exhaust lobe seems to have gind up the lifter wich is a lot shorter now.

Dennis.

The only oils out there now with zinc and manganese are Rotella & Delo. If you are not using them with a flat tappet cam then you are running a risk of losing a lifter or lobe on break in. Big oil has Ditched us old flat tappet guys because we are so few and all the new stuff has roller cams and they can save a penny or two...SCRAP

Sometimes cams & lifters do not get there proper heat treatment, so you will wear through the surface hardness on the cam could have been a bad batch of lifters(but not a commom problem) more likely the cam was bad.
Are you running standard/stock valve springs? What is your seat & over the nose pressure on the springs?

Yes i am using stock valves and springs, but i have not got the equipment to mesure the pressure on the springs and the machine shop is closed 3 weeks for the holyday.
Anyway i e-mailed Paticks about it and send him some pictures i will need a new cam and lifters now anyway and i hope i can finish it up before the end of my holyday.

Dennis.

Dear Dennis;

Patrick's sells 3 cams for the early engines.

The M4-F is for the pre 1955 engines. The F 298 is an 'all out' upgrade for the pre 1963 engines.

I can't recall the (F-29?) one in the middle, but that's the one you want for max power & a smooth idle. It's best to run the springs, lifters & pushrods that are designed for those cams as well.

Stock springs will 'float' the valves at around 4000 RPM+/- and shimmed ones can 'bottom out' & bend a pushrod.

Also; multi-grade oils don't work well in the early engines, so stay with SAE 30 in mild climates.

Good luck.

I had a similar trouble with my 261 Howard 3/4 cam from Patricks, turned out to be that the tubular push rods were mushrooming the rocker arm adjusting balls. Went back to stock original push rods and it's been fine since. Was ready to rip out the cam, then found the problem.

It seems that SCRAP was right about the oil.
I just talked to Patrick about what happend and he had the same story.
Now i am going to look for som oil that do have zinc and manganese in it. and if i can get that brand down here in the Netherlands.

Thanks,

Dennis.

SCRAP,

You are talking about rotella.
Is this the Shell Rotella single grade oil?
Than i should be using the rotella sae 30 or not?

Dennis.

Dear Dennis;

Dello (SAE 30) is a good one too. It's a Standard Oil/Chevron product made for commercial vehicles.

NO multi-grade (15-40) is all.

You bought it about 1 1/2 years ago?

Around that time there were several reports of people wiping out M4F cams (and possibly others).
At the time, I heard that some had used lifters made offshore, and that the hardness of the lifters were not correct. I believe I also heard that some of the cams hadn't been hardened properly either, but I can't confirm this.
I would hope that Patricks will help you straighten this issue out.

Technically, the M4F is practically the same as a stock 261 camshaft. I doubt you would ever tell the difference between them, especially with stock intake and exhaust. There's nothing wrong with using the M4F, but with the extra 26 cubes, you can step up to a slightly hotter cam and still be happy. Do not use the F298 unless you are going to do alot more to the engine.

Since the M4F is basically stock, I don't see why you would have to run stiffer than stock springs unless you wanted to.

If the head has been milled and/or the block decked more than around .020" total, then there should be a shim used under the rocker stands to compensate for the milling, otherwise it could add to your valve train geometry issues...

Did you use anything on the camshaft and lifters for break in?
Did you prime the oil pump?
What rpms were you running it at during initial break in?

Here is a page out of a 1955 shop manual on oil viscosities, etc...
http://pic20.picturetrail.com/VOL1205/4415295/9337405/175551634.jpg

Check the card that came with the camshaft also.

Gearhead;

I used some lube the engine shop gave me.
I have primed the oil pump, i made a bit for the drill and primed it for 15 minutes.
The rpms where somewhere between 1000 and 1200 rpm fast idle.
Strangely the first time there was no card with the cam so i hope that this time there is one.

I know there is not much to gain with a M4F but that is not what i am looking for right now.
My intention is not to go over the 50 m/h.
And i want to keep the rpms around 4000 max.
so i am still looking for a small (max 2 inch) rpm and vacuum gauge for under the dash.
so i can monitor the engine while i am cruising along.

Dennis.

Well, it sounds like you have everything under control. You shouldn't need to prime it for 15 minutes though. Just long enough to get oil to squirt out of the rocker arms is good enough.

Right, the M4F should be fine for your purposes.

I can post a picture of the card that came with my F298 if you need me to.

Gauges can be found at www.jegs.com or www.summitracing.com as well as others...

I just installed a COMP cam, and their break-in recommendation (in addition to applying their special break-in grease during assembly)was to immediately run the RPM up to 2000 and hold it there for the first 20-30 minutes. This ensures that enough oil will be slung off the crank to keep the cam lubricated.
Good luck!

Dear Dennis;

The F-290 cam # was right and is the upgrade for the 261 engines (non racing).

You need the heaver springs because the stock ones aren't strong enough for the higher RPM your engine will see (sometimes) etc. As stated; the (tube type) pushrods are a plus too.

Whatever lube you use to assemble will be washed off by the time you adjust the valves & get it on the road. Simply set your idle a little higher than 'normal' for a while is all.

How/why do cams go flat in 200 miles is anybody's guess. Metal fatigue is probably the #1 cause, I would think.

You have to remember; these engines were never ment to do what "we" make them do. Now & then things just go wrong is all.

Good luck.

There was a recent article in Hot Rod magazine about the rise of cam failures. The root cause was poor lifter quality (offshore suppliers) and decreased anti-wear additives in oil (ie. zinc). The recommendation was to use diesel oil which still has the additives. I know that some of the performance oils still have the zinc. If you do a search on google, you will find listings of ingredients for major brands.

John, do you have any quantitave data to support your statement that multi grade oils do not work in early engines?

Dear Jayson;

Yes many years (50) in the business.

They "work" but don't lubricate as well as 'standard' SAE 30 does. My guess would be that the 'early' cast iron engine was not designed for the multi grade (lighter/thinner) oils which began as a US Army idea in WWII.

Now; in a 'freezing' climate, not so. SAE 30 is pretty thick (at start up) for that usage.

You need to remember; in that era there weren't people running around doing "study(s)". We just did what worked best for us and others in the industry..

From the early 50s through the early 60s all commercial vehicles and most passenger cars used 30 weight oil. Most 'racers' used Valvoline 30 on & off the track.

By 1963 the engines changed to the 'full flow' oiling systems. Today many use multi-grade oil in them, for all climates with great success.

Try this test. At room tempature put a teaspoon of 30 weight & one of multi grade on the same incline. The multi-grade will run off the table while the SAE 30 stays a while.

Try Dello 400 SAE 30 in one of yours and see.

why do cams go flat?? if any one can come up with the answer they will be very rich. in the 70's so many cams were lost we would start them and break them in with old valve springs then change over to the good springs. and it was not only new cams either. i had more then one motor come in with the lobe gone after 15,000-20,000 mi. most were #5 exhaust lobe on a sbc but then i had one where #2 intake went.


is it bad cams? bad lifters? who knows? maybe there is a bad run of cams or lifters now and then. but who can prove it. the cam companies say it is the oils fault. the oil companies say the oil meets spec.


all i know for sure is the guy at the end of the line, as in you and me get the short end of it.

Well, when you buy a cam from anyone, they usually will not give you any waranty unless you bought there lifters.
Even though there are only a few actual lifter manufactures, they just get reboxed in the own Co. boxes.
I believe it was that way years back.

you are more right then you think. there used to be 3 lifter manufactures back then. now there is only one. the price of lifters almost dubbled when trw went under. there were also not that many cam grinders. the cams also reboxed and sold under differnt names.

Gentlemen;

I think Brian was probably right about the 'offshore' lifters getting into the mix.

When a lifter goes bad, the center is "hollowed out" and it acts like a cutting tool for the cam lobe. This is worse with dual or heaver springs for our applications.

In the 'fifties' we just had stock lifters to use. They had to be checked regulary due to this condition.

I guess the answer is to find a way to check the face of any lifter for hardness prior to instalation.

Does anyone know if SBC lifters will fit the 'later' six?? If so, we could get ours from a Hot Rod supplier like Jegs, Summit etc.

Oil may have changed but I don't think that fact would single out a lifter/cam & there would be damage elsewhere as proof.

Counterfeit parts are everywhere these days. The aircraft industry has gone crazy because of it.

Expletive deleted

John ,
the 194-250 Chevy six cylinders use SBC lifters.
I would think the 292 engine does also?

H;

Well that's a step forward then.

Do you know when/why TRW stoped making car parts??

They were bought by Federal mogul. There new name is speed pro/sealed power. They carry most of the old parts and the numbers are the same.

Dear John;

Great, now we all know who/where to go etc. Sealed Power has been around a long time and is an American owned/opperated Co.

Thanks!

PS: While were all on this topic; Has anyone ran a Crower cam with solid lifters & double springs in a 250/292??

John,
"PS: While were all on this topic; Has anyone ran a Crower cam with solid lifters & double springs in a 250/292??"
What is your question regarding this question?
What do you want to know?
Hank

H;

I was curious on the results, as there was one on e-bay etc.

I decided not to get it, even though it was a bargain.

Thanks.

J;
What was the item number on Ebay?

I don't have it any more, auction closed. The complete kit (cam, springs, retainers, shims, lifters & install lube + paperwork) sold for $163.00 I think.

I'm going to wait till this lifter situation sorts itself out and do some more research.