Engine seized 2 miles after rebuild
- Thread starter Merc Cruzer
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Merc Cruzer
Well-known member
Just as an update: Cause: plug in the passage way. I got lucky and rebuild is to have the crank polished, new gaskets and rod and main bearings....plus alot of cleaning.
Merc Cruzer, I don't mean to beat a dead horse, but I just want to clarify. You had the plug installed as per the 95% modification but you did not have the filter plumbed in? Or, did you have the filter plumbed in stock wise, returning the oil to the pan? Maybe this was covered, but with 7 pages of posts and my having the attention span of a parakeet, I missed it.
GOSFAST
Well-known member
Hi "36", just to clear it all up, you must remove the "plug" IF you do not have a filter in the system. The plug, when it is in place, stops the oil from reaching the main galley and the rear main gets oil only!
When you use a filter in the line you need to have the plug in position in order to direct the oil to the filter on one side, in other words, the oil pressure "hits" the plug is "forced" to pass through the filter, after the oil passes through the filter it returns to the opposite side of the plug and continues on to the main passageways!
I've only done the modification to 2 blocks as of today, one is still be built and the other has been in the Merc for a few months now! Works flawlessly so far!
(Add) You must maintain the integrity of the oiling system by keeping all the passageways equal in size, not good to "step" down any orifices!!
Thanks, Gary in N.Y.
P.S. The one that has been running with this modification, runs with 35# pressure hot, idling, and 55#/60# hot "cruising"! This is with the standard "M-19" pump, no mod's to the pump, also with .003" clearance on the mains and .002" on the rods! This is a 4.250" Eagle crank/Scat rod, 292" stroker! Also has NO temp issues!
Hi Gosfast, thanks. I understand how it all works because like you I have modified blocks, 4 so far with two of them for the full filter system that requires the plumbing run on the outside of the block inside of the flywheel. (I posted pics earlier in this thread of a modified block with the spin on oil filter conversion I am making for them.) I am currently running my 8BA with the full filtration and mine has about the same numbers as yours except the hot idle drops to 10 to 15. That is probably due to the 1/16" hole I drilled in the oil tube plug behind the cam gear for a little extra oil directed to the timing gears as per Mike Davidson's flathead book.
So, like you, I understand the system, I was questioning exactly what set up Merc Cruzer had when he discovered the problem. Did he have not have a filter on it or if he did, was it plumbed like stock routing the oil back to the pan? Sorry for any confusion.
So, like you, I understand the system, I was questioning exactly what set up Merc Cruzer had when he discovered the problem. Did he have not have a filter on it or if he did, was it plumbed like stock routing the oil back to the pan? Sorry for any confusion.
Merc Cruzer
Well-known member
36bird and gofast:
The block was drilled for the 95% filter since it was out of the car for the rebuild (for use at a later date), but then plugged to use the standard configuration. Unfortunately the plug used to block the line when the 95% filter is in place was left in....thereby causing the oil starvation to the front and middle bearings. The interesting thing was that only the middle bearing seized, for some reason the front bearing was getting enough oil to remain functional.
The block was drilled for the 95% filter since it was out of the car for the rebuild (for use at a later date), but then plugged to use the standard configuration. Unfortunately the plug used to block the line when the 95% filter is in place was left in....thereby causing the oil starvation to the front and middle bearings. The interesting thing was that only the middle bearing seized, for some reason the front bearing was getting enough oil to remain functional.
GOSFAST
Well-known member
Hi "Merc", the center main is directly supporting 4 cylinders in the firing order, number's 2 & 3 and 6 & 7, the front main supports mostly the two front cylinders and partially the numbers 2 and 6. This causes more "loading" on the center main brg.
Not certain if you noticed also that the "Flattie" crank has an incorporated design from the early years that has now carried over to the "racing" BB Chev's!
The center main on the 3-main setup has "full" counterweights just like many of the aftermarket BB's now use! This keeps the shaft from "flexing" during normal use! Also aids in balancing the ***'y! Old "Henry" realized these counterweights were a necessity to "keep it all together"?
A few years back, around 1999, we did a circle-track Flathead that saw continous 4800 RPM runs, so we fabricated a "girdle" that "rested" on top of that center main and straddled it and tied the pan rails together along the outer edges to support the weak section of the "webbing" and the threads in the center of the casting. Engine still runs strong after some 11 or 12 years! A good friend of mine was running it on the stock car circuit up here in the Northeast!
(Add) I would like to add this also, if you are not running the stock fuel-pump pushrod you must at least block off that section of the block where the bushing is located! There will be a small internal leak at that area affecting the overall oil pressure! (See the photo below)
Thanks, Gary in N.Y.
P.S. Good luck with your repair, should go fine now! Just look at all the knowledge you and the others gained up here, priceless, really.
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Merc, I get it, the plug was in and you did not know it. But, what I am asking is, did you have the oil filter on the engine when it seized? If you did, was it set up for the stock configuration? That is, did the oil come up from the pump and go to the filter only to be returned to the pan while all the other oil could not go into the system because of the plug? None of this matters so long as you have it figured out and fixed. I'm just curious of the configuration you had when the failure arose. I see in your avatar a stock canister filter on your engine so I am just assuming (but seeking verification) that you tried to run your modified oil system engine with the plug in going thru the stock oil filter set up. After this I am out of ideas on how to ask this question.
flatjack9
Well-known member
You will have pretty much the same oil flow out of that hole whether the pushrod is in or not, since the pushrod is not a tight fit. Doubt you would be able to measure any difference in pressure with or without the rod in. With the rod out, you'll get a lot more oil flying around in the valve chember though.
The 95% full flow conversion seems to have been "invented" a few times, but the original design by the Ford engineers was well tested by at least five armies on our side, and if the slight decrease in diameter of the Ford fitting from the block oil port size caused a problem, it would have been simple for Ford to increase all the drilled oil passages in the block at any time in the more than ten years it was in use. Using the thimble type fitting pretty much solves any surprises, maybe years down the line, by a grub screw hiding. ..B.
Merc Cruzer
Well-known member
36bird:
If you did, was it set up for the stock configuration? That is, did the oil come up from the pump and go to the filter only to be returned to the pan while all the other oil could not go into the system because of the plug?
The answer is Yes and Yes
I see in your avatar a stock canister filter on your engine so I am just assuming (but seeking verification) that you tried to run your modified oil system engine with the plug in going thru the stock oil filter set up
Actually, I was running the fully original stock system, where the oil comes up from the pump to the stock filter and then is returned back to the oil pan. This system allows the oil that is not going to the filter to go through the opening in the block to the tube that feeds the front and center bearing along with the cam etc. The problem was that since the block was drilled for the 95% filter system that required a plug in the opening in the block to the tube that feeds the front and center bearing along with the cam etc. and the new hole drilled to allow for the return line of the 95% filter.
The pictures show the engine when I did a partial assembly and before I replaced the oil lines with new steel lines. You can also see the hole in the block that was not yet plugged (part of the modification to the block for the 95% filter system) and if you can imagine a plug in the oil passage way in the block from the feed line to the filter and the unplugged hole then you have the configuration when the engine seized.
The bottom line is that none of the system for the 95% filter was being used at the time of the engine failure....only the origional filter system was in use, but with a plug in the passage way (that should not have been there) to feed the cam and bearings.
If you did, was it set up for the stock configuration? That is, did the oil come up from the pump and go to the filter only to be returned to the pan while all the other oil could not go into the system because of the plug?
The answer is Yes and Yes
I see in your avatar a stock canister filter on your engine so I am just assuming (but seeking verification) that you tried to run your modified oil system engine with the plug in going thru the stock oil filter set up
Actually, I was running the fully original stock system, where the oil comes up from the pump to the stock filter and then is returned back to the oil pan. This system allows the oil that is not going to the filter to go through the opening in the block to the tube that feeds the front and center bearing along with the cam etc. The problem was that since the block was drilled for the 95% filter system that required a plug in the opening in the block to the tube that feeds the front and center bearing along with the cam etc. and the new hole drilled to allow for the return line of the 95% filter.
The pictures show the engine when I did a partial assembly and before I replaced the oil lines with new steel lines. You can also see the hole in the block that was not yet plugged (part of the modification to the block for the 95% filter system) and if you can imagine a plug in the oil passage way in the block from the feed line to the filter and the unplugged hole then you have the configuration when the engine seized.
The bottom line is that none of the system for the 95% filter was being used at the time of the engine failure....only the origional filter system was in use, but with a plug in the passage way (that should not have been there) to feed the cam and bearings.
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Merc Cruzer
Well-known member
GOESFAST:
I am using the original fuel pump with an electric back up...
I am using the original fuel pump with an electric back up...
Merc Cruzer
Well-known member
36bird:
Had some time this morning so I thought I might do a partial assembly of the engine to show you the oil filter configuration at the time of the seizure. I have laid the grub screw on top of the block above the passageway of the blocked line....hope this explains the issue.
Had some time this morning so I thought I might do a partial assembly of the engine to show you the oil filter configuration at the time of the seizure. I have laid the grub screw on top of the block above the passageway of the blocked line....hope this explains the issue.
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I have followed these post from the beginning and I have a couple of questions.
I have what is referred to as a Canadian block. It has three threaded holes on the bell.
The two on the left ( one vertical and one horizontal) have my oil press sender and the oil line to the old style filter. The other one has a pipe plug in it. It seems to work OK.
My question is why did Ford use a grub plug in the first place? On my block what was the other hole for? This block was NOS when I got it. Nobody drilled anything
Thanks
Dick
I have what is referred to as a Canadian block. It has three threaded holes on the bell.
The two on the left ( one vertical and one horizontal) have my oil press sender and the oil line to the old style filter. The other one has a pipe plug in it. It seems to work OK.
My question is why did Ford use a grub plug in the first place? On my block what was the other hole for? This block was NOS when I got it. Nobody drilled anything
Thanks
Dick