Fuel's Winter Project: Build It Before It Blows

[BruceH]

Nothing obvious. I am thinking it was me starting the dyno pulls too low in the rpms putting too much load on the engine down low lugging it. Cylinder temp went up because of this and caused the only rings I used to fail. That's my initial thought. Either way I am taking full responsibility for this. I built everything so its on me.

Did the crankcase pressurize? Have you pulled the valve cover to rule out a valve issue?

 

[JoshK]

The crankcase pressurizes when you try to pressurize #4 for a leakdown

 

[swflastang05]

The crankcase pressurizes when you try to pressurize #4 for a leakdown

^^That's no beuno. Did you pull the valve covers yet to confirm there's nothing wrong underneath and when you did the leak down to make sure all 3 valves are in fact closed?

 

[JoshK]

Haven't done anything other than push it in the garage. It is really starting to bother me about what is actually broke, but my very small garage isn't in car building mode right now

 

[Doug M]

Sorry brother! Got to get it figured out, too much invested now!
You will get it, no doubts!!

 

[JoshK]

 

[BruceH]

Since you are the guy tearing it down I'd imagine you have some ideas about what happened.

From here it looks like maybe a ring or ring land broke and galled up the side of the piston. How do the other pistons look? How about the bearings?

 

[weather man]

Damnit, your harshing my guts Josh!

 

[JoshK]

I was driving it on the dyno and was starting the pulls too low in the rpm with too much load. It was like the engine was getting big boost in overdrive for comparison. Just straight melted the piston. Ring land and rings are still in tact, just melted the side of the piston. Bore looks to only have deposits of aluminum on it, no gouges, so I believe a hone will clean that up. I still only have the one rod and piston combo out. Bearing has quite a bit of material in it, but the crank journal looks new. Evaluating head/cam journal damage now.

 

[JoshK]

I pulled a couple cam caps. Not sure how bad this is? Fingernail does just catch





These are the #8 rod bearings. #4 cylinder is the one that failed FYI

 

[BruceH]

I'm wondering how long it ran with broken pump gears after the piston went. I've seen heads look like yours as a result of the wrong oil/pump/clearance combo over time but imo the top end got starved when your gears broke or debris got into the oil and eventually took the gears out along with scarring up the cam journals.

Anything that catches a fingernail is at least .002-.003". It might be time to look at those 3v cam bearings on ebay for $70.

 

[JoshK]

I got the remainder of the pistons out of the block tonight. #5 piston is melted the same way as 4 but not quite as bad. I called and I can get the pistons individually. Also called my machinist and he got me the weights of the pistons I have to match them up. He also said that with it just needing a hone to clean the bores up he will be able to get me in and out pretty quickly.

The heads and cams I believe are fine. I am going to be upgrading to Fox Lake stage 3 heads along with some much stouter cams more fitted to my setup. I will give more details on this after the first of the year and I can get them here.

There is going to have to be a few dollars spent, but I won't be cutting any corners this time. I am going to be going with a steel top ring with Napier second ring this time instead of the only ring stack. Also will have the billet oil pump gears this go around.

Also, for the record, there is NO signs of detonation in this engine ANYWHERE

 

[weather man]

I got the remainder of the pistons out of the block tonight. #5 piston is melted the same way as 4 but not quite as bad. I called and I can get the pistons individually. Also called my machinist and he got me the weights of the pistons I have to match them up. He also said that with it just needing a hone to clean the bores up he will be able to get me in and out pretty quickly.

The heads and cams I believe are fine. I am going to be upgrading to Fox Lake stage 3 heads along with some much stouter cams more fitted to my setup. I will give more details on this after the first of the year and I can get them here.

There is going to have to be a few dollars spent, but I won't be cutting any corners this time. I am going to be going with a steel top ring with Napier second ring this time instead of the only ring stack. Also will have the billet oil pump gears this go around.

Also, for the record, there is NO signs of detonation in this engine ANYWHERE

Give some thought to swaintech for the pistons and combustion chamber Josh.

 

[05stroker]

I got the remainder of the pistons out of the block tonight. #5 piston is melted the same way as 4 but not quite as bad. I called and I can get the pistons individually. Also called my machinist and he got me the weights of the pistons I have to match them up. He also said that with it just needing a hone to clean the bores up he will be able to get me in and out pretty quickly.

The heads and cams I believe are fine. I am going to be upgrading to Fox Lake stage 3 heads along with some much stouter cams more fitted to my setup. I will give more details on this after the first of the year and I can get them here.

There is going to have to be a few dollars spent, but I won't be cutting any corners this time. I am going to be going with a steel top ring with Napier second ring this time instead of the only ring stack. Also will have the billet oil pump gears this go around.

Also, for the record, there is NO signs of detonation in this engine ANYWHERE

So, are you thinking it was ring failure that led to this?

 

[JoshK]

No, it was a poor dyno operator along with me starting the pulls at too low of an rpm.

 

[TheBlackPearl]

What rpm did you say you started the pull at?

 

[weather man]

Josh, my thought was that the oil pump failed, resulting in all the damage you see. I asked Danny at DB performance to look at the pics and give me his opinion. I didn't tell him what I was thinking.

Brian,
My honest opinion......Oil pump broke and caused everything you see! ?There is no damage to the top of the piston in the one picture. If there was too much heat and shit started to melt it would do it to the top of the piston 1st. All the heat is on top not the sides.


Too low of RPM wouldn't do this damage. Too low RPM, high boost and a F'd up tune would start burning the top of the piston creating a cut out in the top of the piston leading into the side. There is no sign of that from the picture I saw. The top outer edge of the piston for arguments sake looks great. If you looked down a bore at that piston I wouldn't see anything, just based on the top of it.

 

[JoshK]

That is all a correct assessment of what I see here. I have some much closer pics of the piston crowns that I sent Manuel last night. I need to get them uploaded to post. There is absolutely no signs of detonation

I was starting the pulls just over 2000 rpm. The engine would struggle to overcome the dyno for a few seconds before the rpms would start climbing.

I could say that the oil pump doing all of this is not out of the question.

 

[BruceH]

So you think the oil pump going would cause piston sides to gall into balls but let the bearings freely rotate and not sieze the motor?

Oil is distributed to the bearings first, they would take the brunt of anything oil pump related imo. A loss of pressure would seize the motor pretty quick and it would of turned the crank blue from heat. It wouldn't keep running after the fact.

 

[JoshK]

The crankshaft is not blued