Spark plug failed catastrophically, cylinder now getting 30psi. Being told engine not worth saving.

[beastlytaylor]

Good day to all!

First time poster, sorry in advance if I'm in the wrong place or am asking a dumb question or otherwise not abiding by community norms. Be gentle.

Last November I purchased a beautiful white 1998 Ford Ranger XLT with a 3.0L with 76k on it. The truck's body and interior are in excellent condition; it was owned by a utilities company in Orlando and seems to have been taken care of really well. I drove it from Orlando to Baltimore where I live in one shot and had zero problems. Drove it regularly since, including some trips to the mountains, and had no problems. Until recently.

On one recent trip back from the mountains, I was experiencing power loss on the highway. At times, I couldn't get the truck to go over 40, even with the pedal down. Other times it would be able to maintain 60 or 70, but it was clear the engine wasn't having fun. Altitude/grade was part of it, but I had made this exact drive before with no issues.

Get back, take it to two mechanics, but without it throwing a check engine light, neither was able to tell me anything. Was seeking out another mechanic who is apparently really good in the area, but he was booked for 2 weeks. Meanwhile the problem seemed to be going away, or at least didn't show itself on shorter highway trips, and became less urgent in my mind.

Fast forward to just a week or so ago, and I get back in the truck after a short backpacking trip in Virginia (2.5 hours from my house). It's idling really rough, and there's a CEL on. Smooths out a bit as I get back from the trailhead to civilization, and decide to just drive it home. Take it back to one of the mechanics who I liked and who has a lot of good reviews. He initially tells me I've got a misfire in cylinder 3 and that all the spark plugs need to be replaced and some wiring but that's it, and I can come get it in a few hours.

When I get there, he says he's got bad news. Did a compression check after replacing the plugs, cylinder 3 has less than 30 psi. Shows me the spark plug he took out of it, and one side of the element that the spark arcs between is missing. It apparently broke off inside the engine, damaging the piston (he guessed anyway, without tearing the engine apart). Tells me that basically I'm SOL, and that the engine isn't worth tearing into to try to save. Take it to another mechanic for a second opinion, he gives me basically the same answer.

I love my truck and want to keep it, even if it means putting a brand new engine in. Is that crazy? The guy I really like estimated 3.5-4k for a fresh out of the crate motor installed. He strongly advised me not to get a used engine as there is no way to know what you're getting (according to him), and that he doesn't put in used engines for people. I could never get a comparable vehicle for 4k obviously. I paid 7k for it initially. I probably would have a hard time finding a comparable vehicle even for 11k (7+4). Again, despite only having it a short time, I love my truck. To me, paying a total of 11k for it, but with a brand new engine, seems worth it. Plus, I happen to basically be able to afford it right now.

Several questions:
1. Is there any hope for my engine?
2. What is your opinion on putting in used engines?
3. Does it sound in your opinion like I'm getting good honest advice from this guy? Any red flags, or red flags that I should watch out for?
4. Am I being stupid and should I just put 4k toward a different car and have a monthly payment?

Sorry for the massive story. I appreciate whatever help or advice you can offer! Thanks!

-Taylor

 

[alwaysFlOoReD]

Im not a mechanic but...
1) Your mech could scope out the cylinder with a video camera. If the piston looks good then;
2) He could do a leakdown test to confirm where the pressure loss is from. It's probably a valve and then a head replacement or valve job is less expensive.

 

[RonD]

Welcome to TRS

It would be a rare occurrence for broken spark plug tip to damage piston, it will make marks on it but not damage it
More likely occurrence it that broken parts caused HOT exhaust valve to bend a bit when it was closing, so it can no longer seal and you get low compression
So "just" a head replacement issue, "just" is a relative term here, lol

Yes, a bore scope can be rented and YOU can look inside or a mechanic can
Google: broken spark plug and piston damage images
To see what to look for

It is certainly possible for piston to be damaged, or cylinder walls, just long odds because spark plug parts are not all that hard, well not as hard as pistons or valves, but HOT valves are easily bent if they close with something trap between them and their seat
They are not designed for stress in that direction

I would get a price on pulling both heads and replacing both, as the high side, then if only one head needs replacing it would be less parts cost, but same labor cost

How many miles on it now, started at 76k?

The bottom end(block, pistons, rods, cams, bearings) are usually good for 400k, but if you were at 250-300k miles I might say "do a rebuild" now, under 200k, no, not worth it, just do the heads

While its in the shop getting heads done I would do water pump and cam synchronizer, the two things that do wear out and are harder to change

 

[Shran]

What they said. Really need to get that head off and inspect it... I bet you can more than likely get away with fixing what you have now. It's possible that the valves are fine and the cylinder wall is trashed or the piston has a hole in it...but not really likely.

 

[mikkelstuff]

76K miles on a 3.0L Vulcan engine is nothing! Unless a scope shows a scored cylinder wall.

Is the engine using oil or blowing smoke? If not, then piston and cylinder wall are likely ok.

 

[19Walt93]

Before investing in a teardown it's worth dosing that cylinder with a couple squirts of oil or ATF and rechecking the compression, if the plug hasn't been firing the injector still is and the cylinder walls could be washed down and that could prevent the rings from sealing. He may have already done it, it's called a wet compression test but it's worth a try if he didn't.

 

[Blitz]

One thing to consider is you said a utilities company in Florida owned this truck before you right? Who knows how many idle hours with A/C on? I have a friend that is a cop that told me never buy a cop car because it might say 100,000 miles on the odometer but the engine is worn out because it has 5000 hours of idle time. I am guessing utility trucks might be same story. My brother just found a 3.0 Vulcan in a junkyard with 80K on it. He ran the Carfax on the truck its in and it was well taking care of. I am thinking if you know history than it will be no riskier than buying a used truck?

 

[bobbywalter]

One thing to consider is you said a utilities company in Florida owned this truck before you right? Who knows how many idle hours with A/C on? I have a friend that is a cop that told me never buy a cop car because it might say 100,000 miles on the odometer but the engine is worn out because it has 5000 hours of idle time. I am guessing utility trucks might be same story. My brother just found a 3.0 Vulcan in a junkyard with 80K on it. He ran the Carfax on the truck its in and it was well taking care of. I am thinking if you know history than it will be no riskier than buying a used truck?

If the engine is maintained...oil changes and fueling via clean injectors....20 k hours on many of our engines....oilfield.

Most can idle 24 hrs sometimes for days or weeks at times.

Idle time dont mean shit to me anymore. ...with full synthetic or semi synthetic oils....and even half ass oil changes.

This is a physical issue.

I have a shit motor from the junkyard...my fault. I knew it when I seen it....it was the lowest mile unit in the system...but from the outside it was a POS....I protested and asked for the 200k plus unit....but I was in a hurry and went to work and was gone a few months ....so if I would have pulled it I would have got a better engine...after the rocky bastard was installed...generally I floor start engines to prevent that. .

Any good yard will warranty the engine as good. Your capacities to deal with it are the breakouts. It is risky

4k.... That is a relative. You can pop 4k for a new engine and this can happen AGAIN THE NEXT DAY. And unless you buy an aftermarket warranty...your on the hook

I don't have alot of money

But I can deal with this old stuff