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Engine Woes - rambling and advice needed appreciated

Millercorey

Full Member
Joined
Mar 15, 2017
Messages
232
Got some shitty news the other day. Backstory - rebuilt the original 302 and installed the NV3550 October 2017. It drove fine, but I probably only put a couple hundred miles on it or so until mid-Dec 2017 when I parked it to tear into the body. If you saw an old post, the day I parked it I couldn't get it started. It would just turn over but never fire. This detail MAY be important.

I tore out the floor pans and installed new metal, redid the body mounts, new knobs/switches, installed painless harness, installed new 23 gallon tank, powder coated the dash and roll cage and got ready to install insulation and carpet. When I pulled the old tank, there was WAY less gas in there than I thought, so I assumed "okay you idiot that's why it didn't start. It was basically bone dry". Before I got ready to reinstall roll cage I figured I needed to make sure wiring was good so attempted to start it up a few times and couldn't ever get it to fire. It turned over for me quite a bit, but occasionally it would just click. Assuming a wiring issue, I started to go through troubleshooting steps. After messing w/ battery cables, I was able to get it to turn over again and decided I was getting a bad connection on the battery terminals. Old battery cables looked horrible anyways so bought a good set from bronco graveyard

Last minute ended up taking it to Damon Hopper near Dallas, TX to re-gear and install disc front brakes, and I mentioned to him I couldn't get it started so he said he'd take a look. If anyone knows Damon, he knows what he's talking about. This post isn't to confirm what he's telling me, moreso to crowdsource possible options, causes, and generally bitch about my luck....

Damon calls me and tells me he can't get it to fire either. Pulled a plug and noted that it had some green on it, and when he tried to turn it over with a breaker bar.....it was SEIZED!!!!!


  • I know I probably didn't make the best decision when I parked the newly rebuilt engine after only putting a couple hundred miles in it.
  • It sat for 10 months before we attempted to turn it over, but I added oil and coolant before I attempted to start it.
  • We had a recent cold snap so I'm hoping I get extremely lucky and Damon goes to mess with it after the holidays on a warmer day and it magically turns over freely. Probably no chance this is even possible?
  • I know the owner of the shop that rebuilt it (City Motors in Dallas), and they're rated very highly on google. It's long past the warranty period, but depending on Damon's findings, I plan on calling him to get his thoughts and options.

So now to my point(s) ---- does ANYONE possibly know what the heck may have happened here? I'm trying to figure out if this is a bad rebuild (head gasket?), caused by my negligence, or just plain bad luck?

If it truly is fully seized, there's nothing we can do right? It's just scrap?
If I have to go new motor, what's the current mood of the community? Early on I told myself I'd go mustang or explorer swap, but then had a change of heart and decided on the simplicity (and cost) of original rebuilt 302 w/ 2 barrel carb. However, now that I may be starting from scratch, I'm thinking we may want to pivot and go to a different strategy.

  1. buy a forum member's old 302, do another rebuild and slap the 2 barrel on there?
  2. buy a roller from blueprint or similar vendor?
  3. buy an explorer motor and rebuild, then stick a carb on it for now until the EFI bug hits me in the future? Then decide on fitech or ford original EFI?
  4. any other ideas?
 

bmc69

Contributor
Bronco Guru
Joined
Jun 11, 2004
Messages
11,852
A leaky intake manifold gasket is one of the more common culprits for leaks developing right away. If it is a head gasket leak, that's unusual for a fresh rebuild...but possible.

Another possibility is a crack in one of the heads that got missed during the rebuild but that's not likely since it was your original engine that was rebuilt, right?

As long as the rebuild didn't take the bore out to .060, it's likely that the engine is far from "scrap". It may just need to be bored and the pistons and rings replaced.
 

pcf_mark

Bronco Guru
Joined
Jun 11, 2010
Messages
3,574
I'm sure this person knows what they are doing but I would want to check the work before calling it seized. Not being able to turn it with a breaker bar sounds pretty solid evidence but maybe it was in gear. Or you have solid engine with a lot of friction and the rest of the plugs are in making hard to turn. Maybe your shifter is something special and they could not get it out of gear but were unaware. It is pretty hard to seize an engine while it is sitting still unless one or more likely several bores filled with water. I would pull all the plugs and douse the cyinders with Marvel's Mystery Oil and let it sit a few days. Then try to crank it once you verify neutral.
 

bmc69

Contributor
Bronco Guru
Joined
Jun 11, 2004
Messages
11,852
It is pretty hard to seize an engine while it is sitting still unless one or more likely several bores filled with water.

But pretty easy to seize with coolant left sitting in any bore...even one.
 

Skytrooper15

Full Member
Joined
Sep 13, 2018
Messages
216
Loc.
Tuscaloosa,Al
I'll go along with pcf_mark on this job except I would leave the plugs out after soaking with marvel mystery oil for a few days then with the plugs out and truck in neutral and the emergency brake on or wheels blocked use the breaker bar and turn the engine clockwise and if it does turn some I would give it a half turn and soak it with marvel for a couple more days and then try to crank it.But before I did this I would find out if any anti-freeze was in the cylinders and if it is I would start looking for the cause of it being there and then pull the intake manifold after draining the coolant,and then pull the heads and see what shape the cylinders were in before I spent lots of money on a new engine.You may get lucky if there is rust in the bores and after freeing the engine pull the pistons and maybe barely hone the cylinders to remove rust and just have to replace the rings and rod inserts.But first drain the oil and see if you see anti-freeze in it.
 
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Millercorey

Millercorey

Full Member
Joined
Mar 15, 2017
Messages
232
So would you say having these problems in this particular engine shouldn’t make one shy away from doing some additional work to it to get it back to running? Like I shouldn’t be scared to throw some machine shop money into it again? Just worried if I should cut bait on this one and save myself future heartache.
 

Timmy390

Bronco Guru
Joined
Jan 1, 2011
Messages
5,609
Loc.
Conway, AR
So would you say having these problems in this particular engine shouldn’t make one shy away from doing some additional work to it to get it back to running? Like I shouldn’t be scared to throw some machine shop money into it again? Just worried if I should cut bait on this one and save myself future heartache.

I know the feeling. I had issues with my new build too.

I would do the marvel mystery oil or ATF with plugs out as mentioned above. Also, drain the water check for oil. Drain the oil and look for water. Get it moving and then take it apart and see what you find.

Its hard to say cut the cord and go a different direction till you know what the issue was and if it's an easy fix or not. It might just need a quick hone, new rings and new gaskets.......

My issue ended up being a cracked head that magnafluxing didn't catch. Heads on/off several times and engine in/out several times too. heads machined twice and block checked and honed twice before the crack in the head showed it's ugly face.

Tim
 

bmc69

Contributor
Bronco Guru
Joined
Jun 11, 2004
Messages
11,852
My issue ended up being a cracked head that magnafluxing didn't catch. Heads on/off several times and engine in/out several times too. heads machined twice and block checked and honed twice before the crack in the head showed it's ugly face.

Tim

Had that happen to me (or a customer, more correctly, but I was the one that missed the crack) a couple of times back when magnafluxing the heads was one of my jobs in the machine shop I worked in. :-X
 

pipeline010

Sr. Member
Joined
Nov 15, 2017
Messages
618
I'm the same way; my mind always runs to the worst possible scenario. Listen to these guys here and be absolutely sure of the problem before you replace, lest you're sitting on a new pile of parts and no fixes.

Mystery Oil is some pretty unbelievable stuff, certainly give that a shot.

When I thought my compression wasn't cutting it a couple months ago (turned out to be a broken idle tube in the carb, duh) I had my eyes on this engine as replacement. It's $100 cheaper now than then ($1699 and free shipping), HO 302 long block and you've already got all the top pieces. A roaring new engine will require tons of other upgrades (brakes, drivetrain, etc). This is an easy, cheap, and good swap imo if it comes to that.

https://www.summitracing.com/parts/mll-bpf30216c
 

half cab

Contributor
Guru Bronco
Joined
Dec 8, 2010
Messages
16,306
Head gaskets are routinely put on backwards. I would have Hopper thoroughly ck it out before discarding the engine.
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,875
Leaky intake will usually show up in cylinders 1 and 4 or 5 and 8. I personally wouldnt condem the engine unless I could verify what went wrong.
 

jagbucket

Full Member
Joined
Aug 9, 2013
Messages
251
If stuck there will be rust on the cylinder walls which even if you get it to run again will wear the rings and cause oil control problems . only fix is to hone/rebore . on the brighter side engine problems are one of the easiest problems to fix. so many options fix yours, get another one rebuilt,buy used/new choice is yours you are in control. body issues you are stuck fixing whats there much rather have mechanical problems you can take out and start over
personally i would never buy a crate engine but thats just me .
 
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