So I got out to it a little bit this afternoon, and checked a few things out.

The timing gears are perfectly aligned. I didn't screw that up. That's actually disappointing, because if that was it, it'd be an easy fix at this point. As it is, now I have to put the timing cover, damper, water pump, etc. back on. But no more doubts in that department either.

The valves are not all the same, but after double checking them, the intakes are taller than the exhaust by about .030...between .030 and .033 (my feeler jumps from .032 to .035 and one was between those two, but the rest were clearly between .030 and .032). Can anybody tell me if that's right?

The 140psi I got on my compression test was with the valves lashed as if adjustable. I doubt I'd get that with the rockers tightened down onto the studs like they're supposed to be.

(Dan...vacuum was an early suspect when I first started out. I plugged off everything from the manifold and searched for leaks, but didn't find any. Then when I lashed the valves like adjustable and had it idling properly, the vacuum guage read 19". That's not a ton of vacuum, but I'd expect worse if there were a leak causing these issues)

I'm suspecting that maybe the machine shop setup the valves wrong. Or they removed more material from the heads than they're owning up to. Less than .010 off the heads and nothing off the block according to them, but unless the valve stems are too long (which I think would be their error) there's been too much material removed from the head/block surface

Update: A little research online shows the intake and exhaust valves are the same overall length. If I remember right, the valve seats are at the same height (intake vs. exhaust) so the valve stems should all be the same height. Anybody know for sure?

Jim

 

As I replied on another thread, the last step in a valve job is to run the head thru a milling machine to set valve stem height to specs. If you grind an old valve and its seat, it will have a high stem. On 302's with the non-adjustable rockers, it's essential they are at the spec'd height. I'm surprised they would skip that step, it is SOP on any engine except a flathead.

 

Jim,
Sorry about your troubles. First thing is valve adjustment procedure is is based on the lifters as much as the head stud style. Different manufactures call for different procedures and pre-load (your 1/4 -3/4 turn after zero lash adjusment). As already noted by all there are several styles of rocker stud set ups on SBF, and all the lifters are interchangeable. You can never go wrong with 1/2 turn past zero lash on a SBF and with everything done that is the method I would use on you engine. If you adjust them this way the various height is no big deal. Back when I was doing machine work/building engines the only ones that you really had to worry about as far as exact height was concerned were shaft mounted rockers and the the true non-adjustable, e.g. the rocker used a bolt through the fulcrum and got torqued down, everything else had some adjustment. You engine is no longer stock, not all parts are factory Ford and you need to make adjustments accordingly to make it run to its best. Personally I have never liked the Haynes over the counter service manuals as there is so much wrong info in them. Never trust a book that uses generic pictures of other engines and bodies in it other than the one the book is supposed to be for. Just my .02 on the Haynes.

As far as everything being out of adjustment after your test drive you need to figure out if the nuts are walking up the studs or are the studs pulling. It is not uncommon for studs to pull with a cam change especially if the rockers were tightened to much (zero lash) and they started pushing the studs, even a little, because once they start they will continue. Measure stud height out of the head and stud height above the nut to determine if the studs or nuts are moving. Hopefully it is the new nuts on the worn studs because that is the easiest fix. If it is the nuts get a set of poly-locks, adjust pre-load to your lifter specs and you should be good. If it is the studs pulling the RIGHT way to fix that is (I hate to say it) pull the heads, pull all the studs, machine the stud bosses down, thread and install screw in studs with loctite and reassemble.

Your compression is fine for your engine, that is a good number for a cranking SBF.

Dan is right, A/F ratio is A/F ratio. If you carb ran good before it should run fine again as far as A/F ratio is concerned. If it acts like it is running out of fuel or some other issue I would look else where, e.g. reduced flow, bad fuel pump, etc.. Fuel components don't like sitting around dry after being put into service, especially if they were marginal before.

Don't be afraid to call me, you have my number from an earlier PM. I have done this stuff for too many years and am willing to help you best that I can. On another note tell you daughter that Heather says Hi.

Good luck.

 

Trying to keep track of what I've shared here, vs. what I've talked to my dad about, vs. what I've talked to my uncle about (mechanic for 51yrs now), vs. what I've talked to the machine shop about gets a bit tricky.

Here's where we're at so far. I'm using the original pushrods and rockers. The rockers show a little wear but do not look worn. Because of the stud issue I had I ended up getting one new rocker and comparing it to my original rockers there doesn't appear to be an material loss. I'm sure some thousandths of an inch have been lost at the tip, but without a caliper to tell me you can't see the difference. Point is...they're in good shape, especially for their age. The pushrods too measure out right and are straight and true with no discernible material loss.

I do have a new cam with the same base circle as the stock cam. A chat with Melling verified that the cam was designed to be a direct swap and use the same lifters, pushrods, rockers, and valves. What's more, the base circle is the same for both intake and exhaust.

I do have new lifters, but they are stock replacements and SHOULD be exactly the same as the originals.

I do have new valves, but according to the shop they got me 5.050 OAL valves, not the alternate 4.873 (I think it's 3) OAL valves, which may be the issue right there. Or the seats may not have been set even. I don't know. At this point they are the wild card.

I went into the shop this morning and talked with the manager and the machinist. They're willing to have me pull the heads, bring them in, check and grind the valve stems as necessary, give me new intake and head gaskets, and send me on my way. However, the machinist also suggested poly-locks (don't know if that's spelled right) which would allow me to adjust the valves (the stock nuts don't lock...oh, and the studs are secure...I've double checked that). I lashed the valves in as adjustable and turned the crank over four times with some Russian Blue on the valve tips to see if the contact points would be within spec with the rockers adjusted instead of torqued down. The contact points seem to be good, so the shop is supposed to be getting me some poly-locks...no cost to me.

Hopefully they come in soon, solve the issues and I can road test this engine before I'm supposed to be taking a 500+/- mile trip in it.

Peace,
Jim

P.S.>>>I'll pass on Heather's greetings!

 

Are we having fun yet?

 

the valve stems of your valves should not be more then .005 difference between the intake and the exhaust
if they are using a longer valve you may need to used a shorter pushrod but the rocker arm geometry may not be correct
lay a straightedge ruler across the top of your valves and then lay it across the retainers that hold the springs they should be real close to straight if the intakes are taller then the exhaust they may have ground the intake seats to far into the head or the exhaust have not been cut far enough to make them the same height
measure from the cylinder head spring pocket to the bottom of the retainer of the valve spring this will tell you if the intakes are to long or the exhaust to short
i would need to know what year heads you have and whether you have rotor cap retainers on the exhaust springs for they are different heights.
when we do heads we like to keep the heights about .005 but the aera
say they can have up to .030 difference
it looks like in the picture that you rail rocker and tapered style rocker studs
every time i tried to used poly locks on this setup because to much preload on the lifter the rocker stud would brake

 

Ax, You're a ray of sunshine.

Jred,
The valve stem tips are between .030 and .034 different between the intake adn the exhaust. The valve springs are about .010 or less different installed height. The intakes are just a shade taller than the exhausts, but I can't get my feeler between them and the straight edge (the smallest I have is .010).

The heads are stamped D0OE-B with dates stamps of 9H11 and 9L28. I honestly don't know what rotor retainers are.

I've got original rockers and studs (except for one...details are in this thread). They're rail rockers and 3/8 studs with 5/16-24 threads (as opposed to straight 3/8 or 7/16 studs).

Jim

 

It sounds like some valves are new, some are old but reground. That would explain the difference. I'm just in disbelief that a shop would not run the completed head thru the mill to grind the stems to spec, I have never gotten a head back from a shop without that having been done automatically, even on engines with adjustable rockers. It makes me wonder if they set valve spring heights?

 

All the valves are new just to be clear. It seems to me like it was done intentionally...the differences between the intakes are immeasurable. The differences between the exhaust are .004-.005, but the differences between the intake and the exhaust are .030-.034

The manager said he didn't think they could grind the valve stems down because they have hardened tips and that would ruin them, but he admitted that he didn't know for sure. The machinist there is one of two, but not the one who did the heads, so there was no asking him.

So far as spring heights, they shimmed several of them and billed me for them so they'd better be right, but I couldn't say for sure.

Eventually we'll sort it out...but I'd sure rather it be sooner than later.

Jim

 

Setting Valve Stem Height

Valve Stem Installed Height

 

the intake and exhaust valves may be the same overall lenth but the lenth of the valve from were the valves contacts the seats may be differant as exhaust valves are thicker at the margin
the margin is thicker on the exhaust because od the extra heat that goes into the exhaust valve and then is transfed to the seat and head
I think that you have all new valves but they didn't cut the exhaust seats deep enough to make the stem height equal
we do fords all the time and the spring seats on the heads are not always cut the same .
we use the dial indecator to set the valve lenth.
on 390 ford heads the spring seats are so far off that we set the two end valves and use a strightedge across the outher ones
their is also 3 different tip lenths on ford 289/302 valves
i would have to look them up in the morning

 

Ross,
Thanks for the links.

J,
They pulled the part catalog out while I was in there yesterday. They had three different part numbers, each with different OAL specs. 4.873, 5.050, and 5.070. They told me they ordered the 5.050 valves for Intake and Exhaust...the +/-.030 difference is probably margin/seat height like you say. That alone should not cause a problem, but if my heads had the 4.873 valves originally (69 to L4 change) then you're looking at .177 difference. Add in the .010 head shave and you're well beyond what the lifter can compensate for. Frankly, I don't think it's that far out, but it's clear the valves are hanging open. And it's clear they weren't ground to be the same height.

 

It's RUNNING! It's RUNNING! It's RUNNING!

I took some video and once I figure out how to get it on youtube and post it here I will.

Got it idling great with no problems and even ran some errands with it today.

I've got an issue that I think is carb, but may be something else. I'm posting it in another thread though to get more specific answers and keep this as more of a build thread...for what ever that's worth.

Anyway...it's running! Video coming soon!

 

What did you do to get it running? I'm guessing polylocks?

 

Jam nuts. Not my first choice. But a workable solution for an engine I won't be racing.

Lashed the valves in as adjustable and she fired right up with no problems. Now on to trouble shoot other issues.

Jim