F100 - Question for Rojo

Here's a question for Rojo, and anyone else that might like to chime in...

I was gonna send this to Rojo in a PM, but thought it might make for good conversation online.


I've been doing some thinking about what I might do with this engine, and thought I'd run it past you. I may address the project in two steps. I'm thinking maybe I simply replace the bearings (the mains and the rod bearings) and put it all back together.

Part of the reason I'm thinking of doing this is, heck most of these parts may be new already because of the recent build, and also just the way some of it looks.

I really think doing it "right" calls for boring out the cylinders, and maybe that will be the next step, which I do next year. It's all so easy to take apart, it might be cool to put it back together with new bearing, and monitor how it runs. Check compression over time and such. Then next year take it all apart, and inspect. Then decide about boring it out and doing it all over again the right way. Might be a cool documentary.

This would also test my skills.

The problem all along might be simply a "dirty build" and those Ford bearings.

Additionally, with some basic measuring, I do think the bore is standard size. This means it can be bored out, yay. I do have a bore guage coming later today which would answer this question definitively.

Let me know your thoughts.

It's very hard to second guess the "Quality" of the build. Obviously it was not rebuilt, maybe not even re-ringed. The bearing issue is the best example of very low grade work in any case. Now the rings will need to be removed off the pistons to make sure no contaminants still remain. Simply blowing the rings out you can't "know" all the trash is out. "Knowing" every aspect of the assembly process is how we warrant our work. The rings must go back on the same piston and in the same groves. If you do take the rings off place them 1/2 way down in the bore, use a piston to "square" the ring with the cylinder walls and check the gap, of Every Ring. If you find any tight rings they should be ground to the proper clearances too. The pistons must go back in the same hole, also they are usually oriented in a particular direction so pay close attention to that or you will have a severe case of "Skirt Slap" if not a complete binding of the rotating assembly. Plastigage the bearings, pressure wash the block super well, I noticed no Anerobic Sealant in the block halves, if that is required I suggest using it instead of the RTV that was used to begin with. Use a Torque wrench to reassemble. The oil pump almost has to have damage I wouldn't think of reusing it. Finally one cylinder had low compression that I have not seen a "Why" posted yet. That must be fixed. My :twocents Bud.

Excellent. I assume by your response you don't think I'm completely crazy! lol

Great advice. I will follow it to the letter, and roll the dice on using the old parts. This will be fun.

Oh, yes, the low compression was due to "visible" head gasket failure, and air being blown into neighboring piston during leak down test. Actually looked bad between #2 cyl and #1, and maybe even between #2 and #3. I'll see if I can find a pic.

https://youtu.be/1VRh7GLSy3g?si=qiHOJRIkj1s6FQX4

Here's the head removal video. And to answer the question I posed in the video, the head gaskets do come in two pieces. Well one piece, but two pressed together into one. They seem to come off as two.

Yes I remember now. I'm trying to get enough done today to slip off and catch a few more crappie this afternoon guilt free. I'm starting to think there was a problem with the oiling to start with and the engine was split to repair that but they just changed the bearings and put it back together. We will never really know though, just guessing. It does make me more concerned about the oil pump not less. I always have so many projects going at once taking time to do one over just can't happen here.

You mentioned oil pump, so what do I do, jump! Yep, that's one thing I've not looked at yet. Looking at the following video, I'll be ordering a new one. I'll take this one apart though just to see with my own peepers.

https://youtu.be/fgIPeYdGeSk?si=Nq237xiTAue_Byx8

Take a look at that. Gotta wonder where those metal pieces came from.

Wow, that’s a lot of metal!

Some of the metal could be left over from whatever the engine went through before this build.

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Originally Posted by DockShootinJack

Some of the metal could be left over from whatever the engine went through before this build.

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Exactly what I was thinking. The previous job obviously was very flawed, who knows when that metal hit the pan.

and pumping all that iron through the motor could be why there wasn't enough oil getting through. Hope the flush job gets it all out, and no passages are clogged or partially clogged to cause further damages down the road.

I watched the video last night and can't believe all that metal is post repair. It looks like the powerhead may have been swapped right onto the pan without even looking inside. Certainly that larger stuff didn't come from the bearings being .010 oversized, also thinking about what I have seen in the past really oversized bearings, even when being oiled well, discolor from the heat. Back to the oil filter, no oil pump output goes right into the filter. Oil pumps are so powerful they all have a spring and ball check to keep the oil pump from twisting off it's driveshaft if the output gets plugged. The volume comes from the depth of the rotors, pressure regulated by the tension on the spring. Oil pumps don't go out, the spring breaks that sets the operating pressures. A oil filter can, the outer housing would just blow off under the pressure. Sierra brand Yamaha oil filters are never used here because one failed, cracked right where the can is rolled to the base, pumping the engine oil out of the engine. Fortunately I caught it, I only use OEM Yamaha filters since, the engines cost too much if you have a failure.

Attachment 478076

Latest pic of the metals found. Found that curly cue piece just now.


I'm tearing apart the midsection so I can get at the oil pan. I broke the mount bolts, I'll show that later.

Anyway, yes, really no heat discoloration on the bearings, just chewed up. Just like we've been thinking, chewed up cause they never cleaned out the oil pan during the rebuild. Dono, but that's where I'm leaning.

Seems like they only drained the oil, and thought that would be enough. The big parts here would never have made it out the drain. So there likely were many more big parts that got fed through the oil pump and to the bearings. That's why the big scars.

That is some big chunks and a ton of small ground up metal. I would have hated to have seen what happened to that engine to cause all of that in the first place

Quote:

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Originally Posted by DockShootinJack

That is some big chunks and a ton of small ground up metal. I would have hated to have seen what happened to that engine to cause all of that in the first place

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That's just a fraction of the ground up metal. And it's just the magnetic stuff I picked up out of the pan.

Do you know what all the metal is from or was that all left over from the first repair job?

I have some big clues. I got the oil pan off and have put my peepers on the oil pickup. I’ll be posting that video shortly. It’s long and taking a long time to upload. But it’s pretty cool.

I need more “hours watched” in order to get the crappie com YouTube channel monetized so you’d be doing me a big favor to take the time to watch the whole boring thing! The end is spectacular, and sparkly!




Sent from my iPhone using Crappie.com Fishing mobile app

I have no real tech advice so I’ll be quiet, but that a bunch of metal. My choice after seeing that is a full on rebuild.

Two of those chunks of metal look like chips off of a lathe. Just don't look like they belong in that engine anywhere

This is intriguing for sure. Watching now…. Oh when ya put it all back together make sure you don’t drop the hook off yer hat accidentally :Rofl

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Originally Posted by BuckeyeCrappie

This is intriguing for sure. Watching now…. Oh when ya put it all back together make sure you don’t drop the hook off yer hat accidentally :Rofl

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Looks like lots of hooks were dropped in it already.

Quote:

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Originally Posted by Slab

Looks like lots of hooks were dropped in it already.

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Tool, etc. maybe the previous rebuilder found left over bolts and frew em in fer good measure? :bash

Quote:

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Originally Posted by BuckeyeCrappie

Tool, etc. maybe the previous rebuilder found left over bolts and frew em in fer good measure? :bash

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I bet your spelling is still better than the engine Butcher I mean Builder.

Me caint speel.

IMHO, the previous owner had to have known what happened. Not completely cleaning the engine mid-section, IE oil pan, then the catastrophic seizure in four months??? And No warranty??? Selling the motor cheap?? Sounds like this person don't need to own anything that requires some semblance of proper Maintenace, let alone close to rebuilding anything...Man what a mess...

Quote:

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Originally Posted by Jamesdean

IMHO, the previous owner had to have known what happened. Not completely cleaning the engine mid-section, IE oil pan, then the catastrophic seizure in four months??? And No warranty??? Selling the motor cheap?? Sounds like this person don't need to own anything that requires some semblance of proper Maintenace, let alone close to rebuilding anything...Man what a mess...

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It wasn't the previous owner, it was the guy he had rebuild it. I seen the receipts. And low and behold, that guy went out of business shortly after the motor failed. Go figure. Do shody work, and your business won't last! :bash