New Engine Nightmare

[stinger222]

489 Stroker with Bravo one. Engine has 2 hrs on it. No compression on cyl 4 and 6, pulled head, blown head gasket, and head is etched about 1/4 in down between both cyl. My engine builder is blaming the intake not being seated properly on the heads (of course he picks the part that I installed after he rebuilt the engine) and it sucked in extra air, leaning out the mixture and causing the gasket to blow...I am not convinced, as I diligently followed the proper torque sequence. When I stopped by the shop today, the guy who built motor was not there, but his other tech was showing me marks on the intake gasket, trying to prove to me the intake was either warped or not installed right. What raised red flag was he was showing me the odd # cyl banks, whereas it was cyl 4 and 6 were the ones that got hot and blew the gasket. If it was sucking that much air to cause a bad enough lean condition to blow a gasket, wouldn't I have heard and air sucking sound/backfires/etc??? The intake was an old 454 mag sq intake, former salt water boat, so I acknowledge its not perfect, but 2 hrs of runtime (nostly idling in the slip trying to figure out what was wrong) to blow a head gasket between 4 and 6 and then etch a hole in head???
I noticed the tech was re doing the studs in the head today when reinstalling the repaired/resurfaced head...Maybe some of the studs came loose or they didn't torque the heads down right the first time??? Given the intake sat on these same heads for years with no prob before makes me suspicious. would appreciate input. This is a 489 with 188 heads, cam from Bob Madara

 

[zbnutcase]

Re: New Engine Nightmare

If the block and/or heads were surfaced without having the intake manifold sides and bottom cut as well can cause misalignment and air leaks.

 

[stinger222]

Re: New Engine Nightmare

So shouldn't the engine builder have told me to bring the intake up to have it fitted/machined??? I'm trying to have some ammo in case he tried to slap me with another bill and blame me for running it lean. Even if it did run lean, not sure it would blow a head gasket like that since I only ran over 3500 rpm for about 20 minutes of the 2 hrs of run time.

 

[adeneo]

Re: New Engine Nightmare

Leakage of air into the intake manifold occurs because the pressure inside the intake manifold is lower than atmospheric pressure, air can then be sucked into the manifold, if it's not properly sealed, causing the fuel-to-air mixture to become too lean. Air being sucked into the intake manifold usually causes the engine to act like it's not getting enough fuel; i.e., running too lean.
The engine may run well at higher rpm's, but the engine dies at idle and will only idle at higher than normal rpm, when the accelarator pump kicks in.
The engine hesitates and dies when you lower the throttle, or hesitates when giving it full throttle from a low rpm.
Difficulty in properly tuning the carburetor (actually tuning will be impossible).
Since the carburetor cannot be tuned correctly, the timing cannot be properly set.
You may get engine "looping" (alternating between high and low rpm).

The engine may backfire, this almost always happens when running lean.
On the overrun, it fails to burn properly so the exhaust system fills with unburned fuel mix, and then a successful spark and the hot exhaust gases sets the stuff in the muffler off with a bang.

Did you notice any of these signs?

On the other hand, did you prime the engine before first startup.
Was the engine already run in, if not, you completely f***ed up if the first two hours was spent on idle with twenty minutes in between running over 3500 rpm.

A lot of engines actually fail during the critical first startup and run in period. This is due to a poor rebuild or wrong run in/first start.

Where the lifters replaced during the rebuild?
where the pushrods replaced?
where the valves replaced?

If not, did they go back exactly where they came from.
All sorts of problems can occur if the guy dismantling and rebuilding the engine messed up somewhere, even poor cleanliness can cause an engine to fail a short time after first start up.

 

[[OBC]Patch]

Re: New Engine Nightmare

A lean cylinder or two is not going to cause a head gasket to fail. Improper torqing, failure to clean mating surfaces,(debri), not checking the heads for warping prior to instalation can cause gasket failure.
Ask your rebuilder how he verified the head surfaces, if he used a machine shop, there will be a receipt. If he just tried to low ball it and stick them back together, ( my guess), he won't have one.
Long wakes, bud.

 

[stinger222]

Re: New Engine Nightmare

Its a roller cam so no cam breakin...Have been trying to break in the rings properly but kind of tough when you loose compression on 2 cylinders so soon

 

[adeneo]

Re: New Engine Nightmare

Breaking in an egine the right way is important, but doing it the wrong way should not cause any problems that soon. As stated above by Patch, running lean for about two hours should not cause head gasket failure, nor should inproper mounting of the inlet.

As long as the engine had water and oil (and preferrably fuel), it should run for more than two hours, even if the carb was'nt set up right, or ignition was a little off. Overheating would of course cause head gasket failure, but doing it in under two hours would take some extreme heat, and fast.

It sure seems like someone messed up pretty bad during final assembly of your engine, atleast that would be my conclusion from the information you have given.

If the people you used for the rebuild are somewhat serious they will fix the problem for you, no matter who's fault it is. Having your work fail after two hours when it should last around twenty years is bad for business, does'nt matter who you are or what business you're in.

 

[stinger222]

Re: New Engine Nightmare

Thanks for the replies. I don't think the guy is going to try to charge me to make things right, however the ph conversations we've had he keeps stressing how I ran it lean and I guess it is only natural to try to shift blame away from the assembly process. I just didn't see how runnning lean for for what amounts to 2 trips past the no wake buoy would blow a head gasket( assuming it even ran lean to begin with)

 

[stinger222]

Re: New Engine Nightmare

got the boat back from the engine builder. He actually had the nerve to ask me if I felt like throwing him a few dollars for replacing the head gasket and putting it all back together. I laughed and showed him how I looked up all the parts from the rebuild and discovered he charged me about $600 more for parts than if I just ordered them at Summit or Jegs and had them drop shipped to him. He immediately backed off and apologized.

Then I get the boat home to fire it up and discover both batteries are dead ( I told him to turn the batt switch to "off" when not working on it because the fridge drains the batteries overnight). The distributor was so loose, when I brushed up against it, it turned 1/8 turn, so there goes the timing!!! Also the TBIV module was just hanging by the wires behind the engine, ensuring the first time I turn the steering wheel the ram would disconnect the wire harness, and the cannon plug was plugged in, but the clamp was nowhere to be found. He told me the boat was lake ready when I picked it up...yeah right. Guess I need to find someone else next time I need a new engine.

 

[300sflyer]

Re: New Engine Nightmare

Guess I need to find someone else next time I need a new engine.

Based on everything you have stated I would have to agree...

 

[TiredoleBoy]

Re: New Engine Nightmare

A lean cylinder or two is not going to cause a head gasket to fail. Improper torqing, failure to clean mating surfaces,(debri), not checking the heads for warping prior to instalation can cause gasket failure.
Ask your rebuilder how he verified the head surfaces, if he used a machine shop, there will be a receipt. If he just tried to low ball it and stick them back together, ( my guess), he won't have one.
Long wakes, bud.

THis

 

[NHGuy]

Re: New Engine Nightmare

I think you might be smart to invest either some time checking, or money having someone professional check, before you run it.
If he's that p'd off, there's no telling how it will have been assembled. Put a torque wrench on every bolt you can reach, might even want to pull the valve cover gasket to check head torque and lifter setup. Verify everything, it's your motor, once it's done you will have years of use. Your builder ain't looking too good at this point.
An ounce of prevention is worth a pound of cure.
Sorry to hear of your dilemma.

 

[stinger222]

Re: New Engine Nightmare

It gets even better! After charging up the batteries, and correcting the other previously mentioned things that my shop didn't do correctly, I go to hook it up to muffs/garden hose to fire it up, starts right up, but I notice after about 10 sec no water coming out of exhaust...I then drive it to the boat ramp near my home back it down into water, start it up, still no water circulating. Get back home, remove rear seat/ie disassemble interior so I can get to raw water pump, remove it, brand new impeller that I just put in there a month ago is burned up/all blades gone...Mechanic must have forgot to hook it up to the garden hose when he tested the motor. Can you believe this. Yet another ruined weekend!! I am demanding all my money back at least for the labor part of the rebuild. This is getting really ugly!!