Hope they fix it but if not...

[wilf leek]

I need you guys to help me understand this lifter "pump-up" phenomenom.

I can understand why, at very high revs, there is not time for excess oil to escape from the lifter, and thus for it to pump up. By very high revs I am talking outside the normal range for hydraulic lifters - 6500+.

However, at normal revs, with engine oil pressure at 75lbs max, I calculate the "closing" force exerted by the lifter on the pushrod to be in the 15-20lbs range (I assume 0.5" dia of the "piston" within the lifter, probably a way out, but good enough).

Now how could this lift valves off seats?

If the preload were to be so excessive that the lifter bottomed out internally, that I can understand would result in valves being held off their seats.
As engine temps reach normal, the preload should lessen (given ally heads) since the heads would expand more than the steel pushrods?

Someone give me a steer here, this is interesting stuff, and I am but a poor ignorant englishman.

[John Poling]

Wilf,

It is just a thought of something to look at. I am not 100% sure of the internal design of a hydraulic lifter rather a basic understanding of the function. I know that there is a small oil galley in the lifter that holds oil and that there is a "feed" hole in the side of the lifter from the block, and also a hole in the "cup" where the pushrod seats, if this has somehow become partially plugged it could cause a pump-up condition. If I remember correctly there is a valve style action (of some sort) inside the lifter that controls oil flow through the lifter. If this is defective it could allow excessive pressure buildup.

Another thought would be that maybe one or more pushrods are not hollow core (or maybe plugged) not allowing oil to pass up through it to lube the rocker arms/valve guides which in turn would possibly cause a pump-up condition. Anyway about it these are just thoughts for things to look at.

John

[tommyboy]

Gerry A. You said you performed a compression check but no mention of a cylinder leak down test. Try the leakdown test. It will tell you where all the cylinder pressure is escaping and potentially lead you towards a problem area.

[Gerry A.]

I have relayed some of your thoughts already and tomorrow when I bombard the builder I will relay the rest. he said he was tearing into the engine on Wed. so I figured I'd give him a few days to find something then call to get the lowdown. I did call someoone else though and this is very interesting and quite frankly extremely plausable.. let me run this one by you and see what you all think sense you have given me so much good information already. I called the cam people.. comp cams. and spoke with their tech.. I gave him the model number and of course he pulled up all the particulars on the cam.. ( they did build it after all LOL), he asked a few simple questions about the rest of the valve train and what heads I was using and here's what he came up with. A normal engine will produce a drop in pressure accross the carb under very heavy load, pulling a steep hill, maybe towing a heavy load etc and cause the power valve to open dumping extra fuel needed to maintain engine rpm and speed. The particular cam that is in this engine however causes the pressure drop almost immediately upon throttle advance, in other words any time I step on the gas the vaccuum seen is virtually nothing therefore the carb is falsely seeing a severe load demand almost all the time and the power valve is constantly dumping extral fuel, which is not needed caused a over rich condition, fouling the plugs and dumping raw fuel into the exhaust which is then burned ergo, the "backfiring" upon acceleration. Man did that make sense to me when I thought about it. It also explains why it doesn't do it when you just freewheel the engine vs. in gear under driving conditions. It also explains the constant black spark plugs and almost everything else. To correct this all I have to do is simply buy a power valve plug and gasket from holley and replace the reg power valve with it.. The only drawback will be that if I do pull a hill I'll have to push the gas pedal to keep the speed up rather than the engine doing it for me.. BIG DEAL>> does this sound like a feasable reason and solution to you folks.. It certainly did to me. Even if it isn't its a very cheap try so what the heck. I do want to thank you for all your help and information and believe me none of it will go to waste.. I'm still having everything you have mentioned checked out.. no stone unturned leaves room for error.

thanks again and take care all.

[Excaliber]

Yup, sounds logical to me. AND fits with the some of the ideas here about a "rich" condition. The question was, if it WAS rich, WHY?

You may have found the answer!

Ernie

[wilf leek]

Gerry - I would have thought that was a pretty extreme cam grind to exhibit that effect, could you post the specs for us ? Matching the power valve to the engine vacuum characteristics is a step well worth doing. It would be a simple matter to temporarily hook up a vac guage and run the pipe back to the cockpit to see exactly what is happening at different throttle openings.

Be careful though - when I did that I was concentrating so much on the guage I nearly drove off the road!

Now you have to get your builder to explain the excessive blow-by.

Luck.

[auto10x]

Wilf,
Lifter pump up will occur, as you mentioned, at high RPMs when the lifter is actually "tossed" "up" by the cam lobe (over powering the valve spring which is supposed to hold everything tight). When the lifter loses contact with the lobe the oil pressure within the lifter causes it to lengthen/expand. When the lifter regains normal contact/operation with the lobe it is now longer and may hold the valve open with resulting "backfire". The engine oil pressure never gets so high that it forces the valve train to hold the valves open, except as described above.

Gerry A.,
The Comp Cams senario may be your answer, but I am in doubt. I don't have a "smarter" answer, but I'm not totally comfortable with their explanation either.
auto10x
Bill

[John Poling]

Gerry A.
I'm with Auto10x, I am in doubt about the power valve idea. My understanding of what a power valve is - is that it controls the flow of fuel to the secondaries when they are not in demand, under no load condition the engine will produce its full vacuum potential and will pull the power valve closed to not allow fuel to flow through the jets for the secondary circuit. If you have a power valve that requires 10" of vacuum to hold it closed but your engine can only create 8" on a good day then yes you will run rich (I'm not a Holley man so correct me if I have this bass-ackwards)however, my thought is that before you would see the backfiring in the exhaust you would flood out or foul plugs or blow excessive amounts of black out of the exhaust or have gas in your oil pan (Do you?). Also I believe it was stated somewhere here that this backfiring is apparent at any load level (full throttle or idle or cruising) correct me if I am wrong. If this is the case I would think that this would eliminate the power valve as the engine would "clean" itself out when you open the secondaries for a few or more moments.

Another suggestion would be to have your engine builder use a degree wheel on the cam PRIOR TO taking the thing apart and verify that the lobes were ground correctly according to the specifications from the manufacturer of the cam. Even the manufacturer recomends that you do this with the installation of a new cam.

Are you certain that you don't have to much lift for the piston/head comb you have? You could have too much lift which would cause your valves to hit the pistons in turn bending the valve head and not allowing the to seat. Again though this does not make sense if you do have a consistant 175 psi in all cylinders.

I post my opinions based on the experiences that I or friends have experienced first hand. I may be way off base here as I know there are a lot more experienced people here than me, so take this for what you can.

In closing I still have not heard anything that would convince me that it is not valve train related.

Don't let anyone push you around when you pay good money for something.

Have a great weekend and I hope that you figure out what is going on so you can start enjoying your ride.

Again, keep us posted when you finally figure it out, this is the way we all learn.

Thank you.

John

[dscott]

I've read through this entire thread and hope I didn't miss these questions. With a stock balancer I have seen them move as much as 50 degrees. I would definitely check TDC and the mark on the balancer. You didn't mention the type of dist or ignition system. If you are getting a popping throughout the rpm band it sure sounds like ignition. I have seen spark scatter cause this type of problem. Ford went to the larger cap on the later engines to help eliminate scatter. If you are running a small cap look inside for tracks, cracks, or anything out of the ordinary. This may be really dumb but have you checked the firing order? With 2 wires crossed the motor will actually run pretty good but under load you will get the symptoms you have. I like to take the simple approach.
Don

[Gerry A.]

Ok, I just got off the phone with the builder and here's what he found when he took the engine apart. Every single rod bearing in the engine was spun, the rods are trash, and the crank has to be reground but the top end is ok.. The one thing he also found that confirmed my suspicion is that there was litterally fuel floating on the oil.. in his words: that engine was so fat it's a wonder this didn't happen sooner.. the oil was thinner than water and doing absolutely nothing to lube the bearings. He totally agrees with me on the power valve theory and said that when they build a total and nothing but racing engine that's the first thing they do is remove the power valves and plug them.

Here's what the pv does from the information I have been able to gather from lots of sources. When the vaccuum drops accross the base of the carb. due to extreme load the engine demands more fuel to compensate for the load. The power valve is designed to open at a certain vaccuum level.. say 5".. when that happens it simply dumps fuel to the engine in addition to the fuel already there from the jets, either pri or both pri and sec. depending on the condition and where your foot is in relation to the carb. LOL. In this particular case the cam is such that the vaccuum drop to almost zero is litterally immediate. in other words under any condition of throttle off idle causes the pressure to drop low enough to open the power valve. Thus it was dumping fuel constantly cause the engine to run extremely rich all the time,(when driving that is,, under freewheel there is no load whatsoever and the drop doesn't occur).
you asked for the cam specs.. here they are:

gross valve lift; intake: .541, exh: .544
duration at .006 int: 284, exh: 296
valve timing at .006 int: 36 btdc open, close 68 abdc
exh: open 82 bbdc close 34 atdc

at 106 intake center line

duration at .050 int: 240 exh: 246
lobe lift int: .3390 exh: .3400
lobe seperation: 110.0

The distributor is a stock ford 351 dist. mag. pickup small cap.. I have check the cap for carbon trails and or cracks and it's in prefect condition. The ignition system is simple, nothing really fancy.. duraspark box. std coil (as far as I can tell) taylor 8mm. spirowound wires ( they measured roughly 200ohms per foot, I check it.) The first set of wires it had on it when I picked up the car I would use as tiedowns for luggage.. they measured nearly 3k per foot. I am thinking of going later on with a set of 8.5mm taylors the really good ones, taylor says they measure between 20 and 50 ohms per foot. They aren't that expensive but for now the ones I have are good.

In a sence those that are saying it's in the ignition are correct because there was so much fuel going in the plugs were having one heck of a time firing even with the good wires. As for the valve train being the culprit, well at this point it's looking more and more unlikely however, I'm having him check all the avenues.

Anyway, I am now convinced that 95 percent of the problem condition was in the fuel system, which lead to alot of other problems. He is however thoroughly checking the top end for the other things all of you have mentioned and hopes to have it completed by next wk. thursday.. ( I won't have to wait till next spring to drive my car again.. YEAH!!!!!!!)

"when you are up to your arse in alligators, it's hard to remember that the first objective was to drain the swamp"

take care all and again thanks for everything.. I love this club and hope to meet some of you face to face one day.. I'll be on this site alot, so if I get obnoxious just send me an email..LOL.

[dscott]

I'm glad to hear they figured out the problem. You're lucky the motor didn't come apart with the bearing problems. Good luck with the car now that things will be normal for you. Have fun and be safe!
Don

[wilf leek]

Ditto what Don said.

At least the mystery is solved.

Now you know why a fuel/air meter can be such a good idea - while you've got the engine out, why not get a bung welded into a primary exhaust tube?

I am surprised it ran at all if it was that rich - to fill the crankcase with petrol takes some doing.
Would not have done much for ring seal either - those rings could be pretty worn, what with all the fuel washing oil off the bores.

Fingers crossed for the rebuild.

[PatBuckley]

From your description of what the symptoms are I don't buy the idea that it was running so rich that the oil got diluted....and then that caused the bearings to go away. Sorry.

It would have been running SO rich that you would have seen black smoke out the pipes....even then most of the unburnt gas would have been pumped out the side pipes....you would have smelled it.

I wonder what happens when rings are installed upside down ??(see my first post on this). I have never done that, so I don't know, but you did say your crankcase was being pressurized somehow - it was blowing oil out of every hole......

Perhaps someone who knows what they are talking about (George?) can chime in....

[Woodz428]

I'm a skeptic as well, you'd almost have to be pouring gas down the cylinders to dillute the oil that much and your eyes would be watering from the excess vapors. I'm also a little leary of the power valve suggestion. I ran a 428CJ with Tri-power for several years and initially getting the carbs set up was frustrating (turned out the carb face where the bowls/metering block attached had been bowed over the years,all three, and didn't allow the power valve chamber to get a good seal and it wouldn't hold the valve closed, after machining flat again it worked great) and although I ate a few sets of plugs my oil never was that dilluted. As mentioned setting the valve up for your vacuum is almost a neccesity, but that sounds almost like one of the floats was sticking. Most of the time when you install a power valve plug you have to fatten it up also so that will make it richer through the whole rpm range.It's purpose is to allow as lean a jetting as possible while giving extra fuel for acceleration and once you hit steady state cruise it closes again. On the pump up issue, the lifters actually have a small "piston" inside that moves a little to allow no clearance and still allow the valve to close all the way, if they can't bleed off some of the pressure they basically become solid. This holds a valve open until the valve action and oil pressure gets to a lower rate, sometimes only after the engine is shut down and pressure goes away in extreme cases. I had a 351C that did this after I wound it up to anything over about 4000rpm and it would literally be running on about 5 or 6 cylinders when it dropped back to idle and would miss for a minute or 2 until the pressure dropped down and stabilized. After measuring valve clearance with the lifters collapsed I installed several shorter pushrods (Ford sevice parts) and the problem was gone. The pushrods come in .030+/- length so it doesn't take much.

[Gerry A.]

Of course you all realize I was just talking to the builder on the phone and that was his description of what he found. I see no real reason for him to lie, exaggerate maybe, cause he didn't want to assume responsibility for what happened. Although he is going to eat the expense needed to get it back to new condition, whatever it takes as both him and B&B are breathing a sigh of relief that someone isn't sueing them in a wrongful death case over what happend that split second a little over 2 wks ago as a total lock up at somewhere in the neighborhood of 90 could have had much worse results than it did. Like I have stated the cause/solution made sence to me and from the way it was acting is quite feasable.. in any case it's a pretty cheap fix and even if it isn't the underlying cause it certainly won't hurt to try it.. You are correct when you say that if I block the power valve I'll have to change the jets. the builder is recommending a +6 increase both pri. and sec. to keep the carb "square" as he called it.. I am considering the purchase of the adjustable block/jet route that is offered by holley. It certainly seems a much easier and more accurate way of adjusting than buying a dozen sizes and installing each one to see what one is right or at least best.. not to mention the gaskets needed each time you change them..LOL. Only prob I can see is if the needle vibrates open or close with the engine running but I think a little clear fingernail polish should solve that or maybe some locktite since it'll be under the aircleaner anyway. and if someone strains that much to find it they need to be slapped anyway.

Going to do a road trip to the mfg. and engine builder Monday so will see in person if things are as they have said. I'll take along this thread as I've printed it out and show everyone there what has been suggested and mentioned. Take care all and again thanks.

[Excaliber]

The power valve theory sounds plausible to me.

Black smoke, soot colored plugs and an eye burning exhaust probably DID in fact occur.

My guess is you were so focused on "other factors" you failed to mention these critical symptoms early on in the thread. It was in fact sometime later that you mentioned the soot colored plugs, all most as an "after thought".

Oil dilution to a very rich condition does fit the symptoms. Severe oil dilution would lead to other probelms as well. Anything that requires lubicration would be affected. Like,,,,,valves?

REAL lucky you didn't throw a rod!

Ernie

[Gerry A.]

Today was a great day in the life and times of Gerry A. I got my baby back today and I want to say that not only am I so happy I could scream but that it runs, sounds and drives absolutely perfect. Almost like a dream.. Everyone involved in this "project" has been super and I want to apologize to all concerned if it seemed like I was comming down on anyone over it.. I really didn't mean to come off like that I just was so frustrated at not being able to solve the problem and when it ultimately lead to the engine locking up it was like driving a stake through my heart. My dream of 35 years had litteraly ate itself for lunch, seriously depressing. The engine builder got everything back together last week and came down to B&B this morning to "tweak" in the carb, timing and other things. They ended up putting 78's in the primary side and 83's in the secondary I believe, the plugs are a beautiful tan'ish brown and she idles and runs smooth as silk. The power valves are both plugged and contrary to some of your beliefs she doesn't lope from light to light.. both B&B and the engine builder have gone the extra mile and then some to put it back together and at last after what seems like forever I can again enjoy driving my dream, although I know it's only been a couple of weeks.. what can I say I really missed her.. There was a show this past wkend also and I just had to stop and say hi to everyone.. Of course they all asked "hey where's the little cobra?" See I'm not the only one that missed her..LOL.

Anyway, all is well with the world again, thanks to lots of effort and time from everyone. I'm also sure they all hate me severely for being such a pain but really I didn't do it on purpose, honest..
and they all stood behind it 150% for which I'm forever grateful.

Well enough for now. I need to get some sleep so I can get up early and drive my baby all day tomorrow.. hahaha. well most of the day anyway. Sure hope it doesn't rain.

[wilf leek]

Great news. Enjoy.

[eds]

Check your plug wires for header contact or proximity.
If you see spots on plug wires they are intermittatly arcing to ground.
Change Ford Motorsport wires to Jacosen or MSD.

[TonyMadrid]

New build of a 351W - only about three or so hours on the motor with only 40 miles on the road. Broke in fine with no problem but since had been running rich, popping through the exhaust, and blowing white to greyish smoke through the exhaust with more on the passenger side ever since. Engine temp runs at 180 degrees and no coolant loss.

Some engine specs: 351 W, backed with a C-4 Auto, Melling HV Oil Pump, Edel perf RPM heads & intake; Edel mechanical Fuel Pump, Comp Cam with 224 degrees and .501 lift on both int & exh; have tried two diiferent carbs - Road Demon Jr. 725 and a Holley 600.

With the Demon I could not get it to behave so I tried the Holley. Out of the box ran fine until engine warmed up then the same problem. Tried to tame the carb by lowering the power valve from a 6.5 to a 4.5; engine pulls about 11 -12 inches of vacuum. Also jetted down from 64's to 62's. Popping stopped but still can't lean it out to stop the smoking that reeks of the odor of unburned fuel. In fact, the pass sidepipe outlet gets saturated with unburned fuel.

Another issue that is of main concern to me is the oil pressure. When cold runs at about 50-60 psi but once warm will not rise above 20-25 psi. I changed the oil and the oil was like water and also reeked of fuel odors. This leads me to believe that the cylinders are loading up with fuel that's breaking down the cylinder wall lubrication and passing into the oil. This thinned oil could account for the minimal oil pressure.

Another observation I made is that the Edel Fuel Pump has twice developed oil leaks at the mounting flange. Both times I changed the gasket, I automatically presumed it was the gasket but now I am not so sure. I say this because after the second time I have now noticed a small amount of oil on the top of the fuel pump. I checked around the mounting flange and it is dry and the mounting bolts show no signs of leaked oil. Could this be a problem with the fuel pump diaphragm that is allowing oil into the pump and it is being pushed out through on of the gaskets between the pump sections? I have read some posts in here about ruptured diaphragms reeking havoc on engines.

I have also read a thread regarding using the wrong oil filter. I do not have a remote system and the standard oil filter that the 351W calls for won't fit between the engine and the frame rails. The guys at the loacl parts house sold me a shorter filter, an STP 16. Could it be that this is the wrong filter? Can anyone tell me what's the correct short filter I should be using?

Well, I know my post is somewhat long, so let me say this. I have problems that are either separate or related and possibly one may have caused the other. Of primary concern is the low oil pressure problem. Can it be a bad Oil Pump or possibly the wrong oil filter? Secondly, what is causing the engine to run so rich? Can it be a power valve problem like Gerry A had or can it be related to a possible fuel pump problem?

As I have only 40 road miles and about 3 or so hours on the motor, I am hoping that nothing major has occurred like what happened to Gerry.

Any help, ideas, suggestions, or thoughts from you gurus will be deeply appreciated. My wife & I just completed the build and would like to get some road time in before Old Man Winter gets here.

Thanks,

Tony