(OT) My broken 14yr old 302 (Pic heavy) UPDATE Feb16

[Thunderfoot]

Some of the older (time-wise) members know that I drag race but for the newer ones, well-um... I'm a drag racer, and I have done it for over 30 years...
Anyway, here is my 68 Mustang that I have owned since 13 years of age (first car) and it has gone through many variations through the years and for this last bit it has been a street/strip car that runs 13.0's here at 3,000 elevation in street legal trim (power steering, mufflers, and all).

There are more photos of it on Photobucket here if you want to look. http://s197.photobucket.com/albums/aa29 ... =slideshow

So on with my engine story;

I built this 302 in it back in 96 and it wasn't built as a killer motor, it really doesn't have any trick parts and has Really small heads on it... I raced it hard for season points here for 4 years, then I have raced it about 9-12 races a year after that, it has a butt load of passed on it... I have had a couple smallish things that I have had to work on in the heads but have not been in the lower end in all this time (14yrs). I was kind of running it to see how long I could get on it, and it showed from the leak down a couple of years ago that it was about do for some rings... Well, this last summer first day of the biggest bracket race we have here (one of the biggest in the NW) it broke second time trail pass. I did a little diagnosis at the track and found it broke the cam at the last 2 cylinders so it was a done deal... As I was working out of town all summer I didn't have the time to work on it so it got left in the trailer until now, as I had to get the shop fixed up so I could do/work on something in it.

Soooo, for those who like to see engine carnage here are some pics of what I found.

First when I got under the car there were scatter marks in the bottom of the pan so I knew it wasn't going to be good... After pulling the pan I found the windage tray was broke both front and rear. this was strange... couple of pieces of the windage tray in the bottom of the pan.



And lots of damage to 4 & 8 pistons.

after getting all the pistons out


Cam came out in 3 pieces cam and all lifters looked great other then it being in 3 pieces, very strange...



Only one intake valve hit the piston and it just barely knocked the carbon off the piston and the valves look ok, I'll know more when I grind them but I'm betting that valve will grind out ok.


So I go to take the crank out, loosen all the bolts and knock them with a mallet to break them loose and

First 3 of the 5 mains busted in half... I think I know why the cam is broke... The block flexed from the mains being broke and flexed and snapped the cam...

The crank looks like new not a mark or score on it, real pleased to see this as no contamination has ever gotten in the oil through the system after all this time. I still need to mic it to confirm but I'm betting it is all good.


The main bearings all looked good even the thrust, the rods were needing replace as a couple were just getting into the copper coating and they were loosing there tension. After 14 yrs of abuse I can't complain one bit.

There are a few more pic here if interested here. http://s197.photobucket.com/albums/aa29 ... %20Engine/

Now I just have to figure out what I'm going to do with all this and I'm on a very small budget.

Once I get something going back together I'll post more info.

Hope you liked the read/story.

[390Nut]

I bet there aren't too many SBC's out there that can do that, but I sure do hear about a lot of SBF/Windsor engines getting run for years at the track without rebuilds.

Heck of a long, hard used life. I'ld turn that block into a coffee table or something, for the shop.

[survivorman]

The Gods of speed demand sacrifices.

[rjewkes]

wow, i thought mine was unfixable after the oil pump drive shaft had pretzeled in half, i never fully looked at why mine failed just that it did and the city got on me the moment i opened the hood. So in went a 390/c6 combo that i was able to trade out for a decent bed off of a 69.



Best motor so far, 2 years and not a knock or other bad sound.

[basketcase0302]

Shayne,
Good story, thanks for sharing. That's a lot of hard core RPM's on one of our "little 302's"!
Glad the damage wasn't worse. I'd been told many years ago that our SBF's had either some cooling issues or oiling issues on the rear cylinders? I remember an old timer telling me this.

Was the oil pressure and temperature still running ok before this happened?

[Brokenarrow]

Good story, that little 302 earned it's keep Are you going back with a stroker?

[71highboy]

thats a nice stang.sorry to hear about the engine but i guess when you race alot things can and do happen.

[69rangerf100]

wow i have never seen an engine break that bad

[forrestbump]

Shayne,

Yes... I did enjoy reading about and seeing your SBF Engine's story. A testament to Ford's superior engines.

Thank You for Sharing!

Larry

[Thunderfoot]

Shayne,
Good story, thanks for sharing. That's a lot of hard core RPM's on one of our "little 302's"!
Glad the damage wasn't worse. I'd been told many years ago that our SBF's had either some cooling issues or oiling issues on the rear cylinders? I remember an old timer telling me this.

Was the oil pressure and temperature still running ok before this happened?

Jeff, I've never heard that before and never seen it with all my SBF in 30+yrs... The temp and oil was all normal.

I hadn't heard about the week main supports until about 7 years ago and then my buddy broke a main cap at about this time in his motor, but he was also using NOS, this was about the time the main girdles for them came out and he put one on his. Then 2 years ago his block broke in half the mains didn't break with the girdle on them but the block spit from the mains up through the cam into the lifter valley, only thing holding it together was the intake and a couple spots not broke on the block. They make lifter Valley supports also for these motors. Seems after you get to making around 350-400 hp you need the main girdle and 400-450+ you need the valley girdle. First thing on my list is the main girdle.

Good story, that little 302 earned it's keep Are you going back with a stroker?

I'd like to build a 331 with some AFR heads for it but don't have the cash right now, so going to put it back together like it was, with another block, new pistons and get the same cam for it so the comb will be just like it was with a main girdle added.

[Ranchero50]

Windage tray metal fatigue...

Parts fall off.

Open headers couldn't hear the parts rattling around?

Lots of dings so the parts were rattling around for a while.

Metal got between the crank counterbalancers and the block web one too many times overstressing the main caps.

Finally the sheetmetal got up between the crank and cam snapping the cam...

Either that or you have more parts floating around somewhere.

Jamie

[DuckRyder]

Dangit - i just lost a long post...

My condolences to your wallet - you should send that into "broken part of the month".

[Thunderfoot]

Windage tray metal fatigue...

Parts fall off.

Open headers couldn't hear the parts rattling around?

Lots of dings so the parts were rattling around for a while.

Metal got between the crank counterbalancers and the block web one too many times overstressing the main caps.

Finally the sheetmetal got up between the crank and cam snapping the cam...

Either that or you have more parts floating around somewhere.

Jamie

Jamie,

She's a full muffler/tail pipes out the back no open headers on her, I like being able to hear things. its also a hydraulic cam so no valve train noise.

Pretty sure the windage try broke from the main caps being broken as it is mounted to the main cap bolts. The pieces in the bottom didn't look like they ever got in the way of the crank, pretty much just fell into the bottom of the pan... but I also wouldn't pass on the fatigue just that it didn't get beat around in there so looks like it just happend.

The extra dings on the stuff is because the stupid thing was still running/idling after it did this and some small pieces/chunks of the cam were flinging around where it happened... Yep, I drove it back to the pits I've had some issues with broken rocker arms before so dropping a cylinder was not a total surprise...(however I had just upgraded to some better ones the first of the year) this one did sound a bit different though and it's my own fault for not turning it off, I probably could have saved the pistons if I had, oh well...

No marks on any of the main caps or webs from any binding or things hitting on them and no marks on the cam either, I'm pretty sure that beings the front 3 mains being broke that the crank was trying to come out the bottom, leveraging itself on the back 2 mains which flexed the block back there and in turn flexed the cam shaft and broke it. Kind of why it broke at the back... I have a buddy that has access to a wet mag and going to check the block but I bet it is cracked up through the cam journals. Also, after looking at the main bearing mounts on the block, the surface is not smooth like it was before on the #2 and #3 ones so I'm thinking they have been broke for a bit before the front one broke which caused all this to finally go...

[brandon.k]

Ouch! That sux about the motor but it sure is a good looking car. Good luck on the rebuild.

[Ranchero50]

That's really weird, honestly doesn't make a lot of sense that a set of Ford iron heads would make enough power NA to do what you have. The 5.0 blocks are HP limited to around 450 crank before bad things happen, but it take boost or juice and R's to split them. Just having the mains crack is strange. Where did you find the cam, in the pan? I can't visualize the cam seperating enough to turn sideways in the back cam bearing and falling through the rotating assy. Seems even if it pushed the soft plug out the back that it would still have trouble turning sideways vs. just binding from the valvetrain pressure.

I'm coming up on 80k miles on my 5.0 build that's around 425 at the crank (390rwhp) and it's still holding up nice in spite of the Autozone crank that was bent when I put it in...

Jamie