Similar problem
 

Hey guys,

I need a little help. Got a new build, running a 351w with Edel Perf RPM intake and heads, MSD ignition and dist, Comp cam (224 degrees and .501 lift on both int and exh). Road Demon 725 carb and then tried a Holley 600. Engine only has been run about three hours, including the initial breakin run and car has only seen about 40 miles of road time.

Problem is this: I cannot lean out the mixture and it seems that the cylinders are loading up with fuel that is seeping past the rings and into the oil. I changed the oil and the oil was thin with a heavy odor of gas. The exhaust is blowing white to greyish smoke that reeks of the smell of unburnt fuel. The White smoke is not coolant as the water level has been constant. Tried the two above mentione carbs with no luck. On the Holley I lowered the Power Valve from a 6.5 to a 4.5 and I jetted down from 64's to 62's. Manifole Vacuum is between 11 and 12 and timing is set at about 13 degrees intitial. Fuel pump is an Edel mechanical and fuel pressure fluctuates between 6 and 7 psi.

My big concern is the oil pressure. When I changed the oild and then started the engine the next AM the pressure was between 50 & 60 PSI. Once the engine reached operating temp of 180 degrees the oil pressure dropped to between 20 and 25 psi and won't rise any higher.

I have seen posts regarding wrong oil filters, bad fuel pump diaphragm, or bad oil pumps being the culprit.

What is a good starting point?

Also, as for the oil filter, I don't have a remote system and the standard filter that the 351W calls for is too large to fit between the engine and the frame rails. The local parts guy told me I had to use a short filter and he sold me an STP 16. Is this the correct short filter for my engine?

As for the fuel pump being an issue, I have twice had to change the gasket at the pump due to a small leak that appears to be coming from the between the flange and the timing case cover. However, this morning I noticed oil on the top of the fuel pump and I could not detect any leakage at the pump to timing cover flange. I don't know where the oil is coming from. Could it possibly be coming from within the pump indicating a blown fuel pump diaphragm?

Any help would be deeply appreciated.

Tony

Tony: check compression of the cylinders.
Jim

Tony,

You've got mail. See a thread named "Hope they fix it but if not" originally started back on July 5, 2003 by Gerry A. As discussed with you on the phone, DO NOT run your engine until you figure it out. It cost Gerry A. an engine seemingly all because of a Power Valve issue.

John

Wow...this is a stab from the past. The culprit was gasoline thinned oil; Demon out/Holley in; problem solved.

I wonder why I never bought the Accusump...? It's on the list for this winter.

Rich

Compression....
 

Thanks Jim,

Compression check is my next step. Will do so later and I'll keep you guys advised of results.

Tony

Hey Rich
 

Hey Rich,

the problem was not solved by taking the Demon out and putting in a Holley. I was able to resolve the exhaust popping but not the rich fuel nor the thinning oil.

Rich,

I had an engine with a similar story as yours and mine eventually became fatal. Did you take a saw and cut your oil filter apart and examine it? If not and you still have the filter take it and cut one end off of it and pull the paper element out and expand the paper filter. Look for ANY signs of brass or copper material in the folds of your filter especially near the bottom.

Taking your oil filter apart is very messy but it could save you thousands of dollars if you catch a bearing going out soon enough.

Clois

Clois,

I don't know if you noticed, but I started this thread 3 years ago. I may not have the neatest garage, but I have taken the trash with the old oil filters out once or twice since then. The engine also has about 12K additional miles.

However...you've piqued my curiousity. I'm due for an oil change and a huge mess. Maybe I'll cut the filter up just to see. Thanks for the advice.

Tony, switching to the Holley didn't totally fix the rich condition on my car, but I think it's just a matter of some addtional tweaking on the jets and power valve. Initial tweaking greatly improved the way the car ran.

Rich

Rich...
 

Rich when I switched to the Holley I was able to adjust it so that the exhaust popping went away. However, I still get smoking and the cylinders are apparently loading up with fuel. In fact, at the outlet of the passenger side pipe the outlet of the pipe becomes sturated with fuel.

This combined with the low oil pressure problem (no more than 20-25 psi) has me concerned. I suppose some would say that the low oil pressure is being caused by the fuel thinning out the oil. It makes sense to me, but what is the fix.

One of the guys in here had a similar problem with double pumper and he completely removed the carb's power valve and blocked it off and that seems to have solved his problem. But before I do that I want to rule out any and all other possible culprits for the condition.

Any ideas would be deeply appreciated.

Thanks,

Tony

Compression Test Results
 

Just ran a compression test and wasn't happy with the results:

Cylinder initial result after oiling cylinder
#1 150 160
#2 150 185
#3 160 175
#4 150 175
#5 150 170
#6 180 190
#7 165 180
#8 160 180

Looks like the bottom end went; rings at least.

Also pulled the filter and cut it open but I didn't find any obvious metal filings or chips. But I did notice that there was a silvery grey matter in the oil. Could this be worn metallic matter from the bearings?

When I cut the filter I didn't know exactly what to look for other than possible metal filings or chips.

Any help with the silvery grey matter will be greatly appreciated.

Tony

Good Morning Tony,

Actually, with the exception of your #1 cylinder wet reading I don't see anything to be concerned about. Before you do anything, I would suggest oiling down the cylinders and checking the pressures again to verify. If you were to tear into it, my thought would be that you will still find the crosshatching in the cylinder bores just as it was when they were freshly bored/honed and that could explain why you're seeing such the increase dry to wet. As for the wet reading, you're right on except for cylinder #1. When an engine is new (not yet broken in), it will have blow by caused by the fact that the rings have not yet seated. Did you put Moly rings in it or did you use the stock style iron ones? If you used the Moly ones, these will take a lot longer to seat and will show the drastic increase in cylinder pressures when wet. Keep in mind that your engine has been washing down the cylinder bores so you will not have as much oil present to help seal the cumbustion chamber. My bet would be that your engine is still okay assuming that it was properly prelubed when it was originally assembled. I would also bet that the silver/grey matter you speak of is normal (for the most part) wear from everything being so new and still seating in. My suggection would be to change the oil and filter, plug your power valve like Gerry A. did and continue to drive it and be very observant of the engine oil pressure and presence of fuel in it and exhaust output and see what happens. I also would suggest to not drive it hard for the first 1000 miles or so. Alot of people tell me that the proper way to break in an engine is the way you're gonna drive it, but these are also the same people that just can't seem to get more than a season or two out of an engine without major problems. I have yet to open the secondaries on mine and I just rolled over 1000 miles the last time I drove it.

Again, try the wet compression test again, as I have seen false readings before. If it still shows similar readings, talk to your engine builder and see what they say. I would also possibly remove the right head and look to see if there is any obvious signs that cylinder #1 looks different from the others on the right side.

Keep in touch here so that this information can be used in the future by other club members and so you can get feed back from other members.
John

Thanks
 

Thanks for the input and hekp. I just called the engine builder and he did not have the time to discuss the issue. Said he had a pressing appointment and asked that I call him this evening to discuss.

I will do that and let everyone know what develops.

Tony

If you have jetted and adjusted your carb then you probubly also adjusted your float levels, so this may not help, but, If they are a little high than fuel will seap and load up your cyls. When I was racing I found that the see through glasses in the bowls help alot and the level should be at the bottom of the sight glass. I was loading up at low RPM's but needed everything I could get @ 7500RPM. I also found one of my floats was holding a small quatity of fuel changing how the float adjusted. Hope this helps.

Engine Problem Status
 

Seems that fuel got into the oil, possibly through a bad fuel pump and it thinned out the oil to the point that it broke down the lube of the cylinder walls and the bearings.

Dropped the pan and pulled two main caps and one rod cap. The thrust bearing finish had washed right off and the bearing was worn so bad you could see copper. The other main and the rod bearing were also worn but not down to copper. Thrust bearing journal is no longer smooth but it doesn't appear to be scored. It appears that it is coated with either contaminated oil residue or bearing material.

Spoke with the machist who built the block and as for the course of action, the machinist recommends the following:

Pull the engine and dissamble it. Examine the cam bearings for wear to determine if they also need replacement. I will also mic the cam lobes and check the lifters for wear to be sure that they broke in well. If they're out of spec, only cure is a new cam & lifter set (about $105.00).

As for the crank journals, the machinist advised me to use 600 emery and lightly polish the journals to see if they'll clean up. If not or if there is evidence of scoring, the crank has to go out for at least a machine polishing, if not a surface grind. According to the manuals I have, cranks can be ground to .020, but the machinist doesn't seem to feel that my crank will be in need of a re-grind. The local engine machine shop charges about $100.00 for the machine polishing.

He strongly advises that since the engine will be apart I should replace the rings, which I will do. As for the cylinder walls, I have to wait 'til I get the engine apart and examine the walls. If the crosshatching is fine, no problem. However, if there is any scarring, he suggests re-honing the cylinders.

Called my parts guy and everything except for the cam & lifters amounts to about $125.00.

So, best scenario is $125.00 and worst is about $330.00.

If you don't hear from me anytime soon, it's because I am locked in my shop working. The Mrs. has already been advised to serve all meals to me in the shop.

Thanks again for all your help and insight.

Your NY Cobra Buddy,

TonyMadrid

Tony,

Sorry to hear about the wash down. Good news is that it sounds as though you cought it before to much damage was done. If I lived closer I would be over to help you this weekend. Regarding your crank, mine has been turned .030 and I have raced it hard in three, three day sessions plus the normal around town driving.
I will be running the same crank at St, Louis in two weeks, so the point is ask a few machinist before you disgard your crank.

I also think you may have underestimated your cost:
gaskets $100.00
rings 100.00
bearings 100.00
crank Polish 75.00
miscellaneous 100.00


Hopefully, you won't need to replace your cam bearings because then you would need to have them pulled out and new ones pressed in. I hope I haven't discouraged you but your costs could be a little more than your estimate. Good luck.

Clois

Thanks for....
 

Thanks for the encouragement and offer to come by and help if you lived closer.

As far as underestimating the costs, I already did the research and here's what I came up with.

Clevite 77 Rod bearings - $28.00
Clevite 77 Main Bearings - $28.95
FM Cam bearings - $10.95
All Summit prices
The following are prices from the guy I deal with at Auto Zone
Hastings moly ring set - $40.00
Felpro Engine Rebuild Gasket Set - $40.00
and he beat Summit's prices on the bearings by about $5.00 on the rods & mains each and $3.00 on the cam bearings.

Not too shabby; huh?

I also spoke with the local machinist and he wants to see the crank and said that if it's within tolerances he'll machine polish it; if not he'll grind it to .020. Either way the cost will be $80.00.

With assembly lube and a rear seal I think I'm getting away cheap. Probably just under two bills.

Thanks again for the thoughts,

Your NY Cobra Buddy,

TonyMadrid