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5.0 Engine Problem 3rd time now!


Josh C.

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Live in: Santa Ana, CA - - - From: Oshawa, Ontario
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1998 Mounty v8 AWD
1998 Mercury Mountaineer 5.0
Yesterday I was on the freeway and my engine started to rattle and a lost power, it didn't shut down but it didn't sound right. As of right now we know that piston #1 broke apart and messed up the cylinder, it's at my mechanic right now. I dont have much experienece on the insides of vehicle engines

Now for the fun part and why I need peoples opinion...this is the third time in 7 years this has happened, cylinder #1 failing. And to make this even more interesting it has always happened on the same part of the freeway. For the locals here in Southern California/Orange County it happens on the Southbound 73 as you go through Newport Beach to the tolls plaza. There is a pretty steep incline for about a 2 miles on this part of the freeway, I have 33x12.5 so to keep at around 60mph I am running around 3000rpm. I'm usually on this part of the freeway at least once a week

So my question is, do any of you know why this happens and what can be modified to fix it?
I don't know if the steep angle for a few minutes is keeping oil or coolant from properly reaching cylinder #1?
Any help or insight would be appreciated

Any help
 


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CDW6212R

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I'm sorry to hear about that problem Josh, and happening three times. My first thought is did it get rebuilt with the same block, and what parts got replaced. I would think a failure like that would be caused by the same thing, and a defect of the block or assembly would be the first likelihood.

I have an old 351W that I rebuilt and had a cam lobe fail on, twice. I built it both times, and after the 2nd time, I swapped in a used 88 HO 302 instead. I discovered a cam bearing in the 351W block that was put in wrong, the oiling hole was barely visible. I didn't check that machine work well enough to catch it either time, so it was on me even though you expect machine shops to be perfect.

What oil pump was installed in the rebuilt engine each time, and what pickup was used, who did the new bearings etc? I'd guess something in the assembly was not right originally, and it didn't get discovered in the next rebuild either.
 




Josh C.

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Live in: Santa Ana, CA - - - From: Oshawa, Ontario
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Nice questions. Each time was a different block. First time it happened on original with about 90K miles right after I bought the truck and we replaced with a junkyard motor because funds were low (it had a bout 80K on it), then the junk yard motor was replaced with a new motor from Rockauto...which ended up being from LKQ (pick a part people). The LKQ motor died after about 50K miles on it. My mechanic is probably going to have a local machine shop who specializes in Mustang engines rebuild the current motor
 




Mbrooks420

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Coolant and oil flow shouldn’t be effected by any road you can normally drive on. Is your overdrive unit burned out? Seems like your RPMs should be considerably lower, especially with 33s.
 




Josh C.

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Live in: Santa Ana, CA - - - From: Oshawa, Ontario
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1998 Mounty v8 AWD
Coolant and oil flow shouldn’t be effected by any road you can normally drive on. Is your overdrive unit burned out? Seems like your RPMs should be considerably lower, especially with 33s.
normally my rpms are in the low 2000's but because of the climb on that part of the freeway its working a bit harder...I have 4.56 gears also
 




974X4BLACKSPORT

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Detonation/ping/spark knock
 




Mbrooks420

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Are these short blocks or complete motors?
 




C420sailor

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If it’s the same block...time to ditch it and start fresh. Not worth the time and $ just to try to fix it and have it blow up again.
 




Mbrooks420

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Was different motors according to the original post.
 




CDW6212R

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Detonation/ping/spark knock

Yeah, that was a first thought, but with three engines, it's odd. Then it sounds like something outside common to all three, like the programming if it's running lean, or the same injectors and one is very weak(lean). That needs some thought, what could do that three times to different engines.
 




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