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1bad914
Based on the pictures can you guess what failed on this brand new motor with less than 45 minutes running time???

So.Cal.914
BUMMER.
type47
the positioning pin that locates the bearing so that the oil passage is not covered up which starves the crank/bearing of oil which causes one to remove engine and start over?

(dowel pin)
Matt Romanowski
Who bought the bearings with double pin holes? Bummer. Was it yours? Did you notice the case not going together easy?
1bad914
Good guess, but the pins were right, they were pounded that way, it started to spin the bearings. Your close...and yes it is my motor and yes it is a bummer. Not a happy guy right now.
type47
if it started to spin the bearings, would that mean the case was align bored and the wrong bearing were installed?
bondo
I'm going to guess oil pump failure.
1bad914
Case was fine, miked it all, it had never been align bored. I dry fit the bearings, I am way anal retentive about my motors. Hint, the simplest part let me down???
1bad914
BINGO!!! Oil pump let me down, not really sure what happened, it was a Type I heavy duty pump. It failed so bad that there was almost no oil in the cooler.

So I started all over with a new 2.0 case and crank...and new oil pump!!!! I was not a happy guy on Friday! I am beginning to think this car is jinxed!!!
type47
what's the wisdom on re-using oil pumps (stock type IV pumps)? do they go bad? can they be re-used as long as they spec out?
1bad914
I usually do not take a chance on using a used one, but in this case this one was baely used, not really sure waht happened with it. If doing a rebuild, buy a new one!
john rogers
That is really painful to see! We used to have many problems with oil pumps with the stroker motors I used to run in the race car before the six conversion. The shop finally converted to an Autocraft 3 stage dry sump system and no further problems with oiling. We used a three stage since it gave us a sump suction and another that sucked off both valve covers and the pressure stage was about double the flow of any type 4 or type 1 pump. Seemed expensive in the short run, but over several years was a $$$$ saver.
bondo
Yikes. Shouldn't you have seen the lack of oil pressure right away? (oil pressure light)
scotty b
I assume you packed it with jelly ?? I forgot it once on a Jeep engine and it locked up within 5 minutes headbang.gif
DBCooper
My guess too, that the pump cavitated.
Jake Raby
The Type 1 pumps can't really fail unless they are installed very, very wrong!

IF the builder first builds oil pressure as described in my video it's almost impossible to have this coccurence..

What I see that caused a failure was that #3 main bearing that was misaligned with the locating pin.. The bearing does not appear to have spun that direction as the dowel pin hole in the bearing appears exactly like those that we have seen assembled with a "missed pin"... The hole just doesn't seem elongated badly enough to suggest anything else- sorry.... Maybe the pics do not depict the whole story though..

I have sold and used THOUSANDS of the modified Type 1 oil pumps and have NEVER seen (not even one) that failed like this.

Where did you purchase the pump, was it one of ours?

I would start looking at all other aspects of that engine prior to reassembly, it may have an internal issue that could have caused this, the only way an oil pump doesn't work is if it's not thoroughly primed or if it's not spinning!

Did you remove the spark plugs and crank the engine for oil pressure prior to start up, or did you just fire it off an go???

Also did you fill the oil filter with oil prior to the priming process?

We use the TI pump in EVERY wet sump engine we build-never an issue.

McMark
Oil pumps can be finicky for the first pressurization. I crank for oil pressure, then let it completely bleed down and crank again. I also watch the oil light constantly. Check Rob's (ConeDodger) motor fire video in The Paddock and you'll see I'm watching the oil light the whole time.
Jake Raby
BTW- IF the oil pressure relief hangs open there will be hardly any oil in the oil cooler as well... Also IF the pressure is very high the cooler may also be almost empty if the engine starts with high pressure and failed before the pressure dropped below 45PSI while the engine was running..

Also, oil coolers start to drain back very quickly due to their position on the engine..

I'd bet this week's paycheck that there is more to this series of events than just the oil pump....

Why is the #3 main jammed right against the cam drive gear?? Is it seized there? Thats not normal by a long shot.
1bad914
Yes I primed the motor until the oil light went out, it took longer than others have in the past, but it did go out. I fill the pump with heavey grease to prime it. I have built multiple Type I and TypeIV motors, and an SBC or two. I have never had a mechnical pump fail like this, I just sat every thing aside and have not really investigated it, I will check all the oil passages for a blockage later. The oil light never went out, it was really wierd that the cooler was almost dry. I had the pins aligned, the number one was elongated also. I may have caused this myself, when it started giving me a hard time my 911 hi-torque starter was banging on it pretty hard, klunk...klunk... The figure 8 look of the number three is wierd, but all of the others were elongated, but not that bad. The case went together like butter???
Well I'll be ordering new parts from you tomorrow Jake, this time a stock 2.0. I hope I have better luck withthis one!! smile.gif
1bad914
I was banging around on the number three, it was in the right place, I was thinking about the oil pressure relief also. This crank, rods and case are going in the garbage after I figure out what happened, what a waste of time and money.

I am not saying that I did not do anything wrong, we all have, but as far as I can tell I did everything right on this one, I crushed a set of bearings once misaligning the pins, I won't do it again. This one will be built in a clean room and EVERYTHING will be miked and measured!! smile.gif
Jake Raby
An engine should NEVER be hard to spin when new!!!!!! The engine should be soo loose on final assembly that it can be spun easily with 3 fingers with the spark plugs out!

Grease is the WORST thing to use to prime an oil pump as it's melting point is typically above 350F so it goes through the pump and galleys slowly almost creating it's own obstruction! Vaseline is the best thing to use because it melts at just above room temperature and mixes with the oil immediately.

BTW- the hi torque starters have more torque but they turn the engine 1/2 the speed of the stock starter and thats not good on initial start up.

Did you fill the oil filter with oil before installing it??

If a short block takes more than 10 inch pounds of effort to spin through it's too tight.. I like 8 inch pounds or less and 5 or less on race engines.....
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