Marine Intake

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L31MaxExpress

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So if the washer doesn't spin you're good to go. And who would think to watch for that?
It is not in their instruction sheet; I would never have thought that would make any difference even if it did.

That being said, extremely disappointed being the R&D for Jeg's Products. I hope they make this situation right, especially since it is their product, has their name on it and was the point of failure. I added a product review showing the broken bolt and explained my dissatisfaction with the product. I followed their instructions to the letter using a torque wrench that was checked for proper calibration before the build started. No other bolts have failed or broken. The bolts were re-torqued after the engine ran on the stand.

I drained the oil this evening. It had approximately 1 gallon of coolant in it along with the 5 qts of oil. This is a recent break as well. The oil was nearly spotless when I changed it about 500 miles ago. The head bolt has failed since then. This might explain why I had the external leak on the passenger bank that developed out of nowhere as well after the engine had some miles put on it that I previously resealed. That being said my fresh engine has now been driven up to 500 miles with coolant in the oil, during which it pulled a 6,000 lbs trailer for over 200 miles. To inspect for internal damage is likely a complete tear down. I will probably pull the heads tomorrow. That being said, the head may be warped, the head surface may be damaged, the block deck may be damaged, the rings have had coolant between them and the cylinder walls, the bearings have had coolant run through them under heavy sustained load. If they ask me how to make it right to correct the situation, it would be a Blueprint crate engine of the same output. Blueprints 396 makes comparable output. I know that would never happen, but that is still what I would tell them.
 
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Singlecab

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Thanks for that link. What program would I need to go forward? l31 what would I need to do to acquire the 0411 tune you mentioned as a starting point? I do have concerns about black bear with regards to the mods I’m doing..being able to go that far outside the box, but for a year I get 40$ tun adjustments. Maybe it’s worth just sending it back with more info, but I’d think the hardware that records data for their fine tuning would be a better way than trying to relay instruction. I’m still unsure of the fact that my injectors have zero seal at the intake port. New orings didn’t solve that. They just sit in there with no detent action. Do they solely rely on the “clamping” force allied by bolting down the rail?
 

L31MaxExpress

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Thanks for that link. What program would I need to go forward? l31 what would I need to do to acquire the 0411 tune you mentioned as a starting point? I do have concerns about black bear with regards to the mods I’m doing..being able to go that far outside the box, but for a year I get 40$ tun adjustments. Maybe it’s worth just sending it back with more info, but I’d think the hardware that records data for their fine tuning would be a better way than trying to relay instruction. I’m still unsure of the fact that my injectors have zero seal at the intake port. New orings didn’t solve that. They just sit in there with no detent action. Do they solely rely on the “clamping” force allied by bolting down the rail?

The injectors have slight resistance. The fuel rail and clips hold them in place for the most part.

As for tuning, I use HP Tuners myself.

Sorry the short replies, will come back later and write more on this. Just getting up and around much for the first time since Friday night. Woke up Saturday morning early feeling terrible. Tested positive for the China virus. I am starting to feel better today.
 

JeremyNH

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Thanks for that link. What program would I need to go forward? l31 what would I need to do to acquire the 0411 tune you mentioned as a starting point? I do have concerns about black bear with regards to the mods I’m doing..being able to go that far outside the box, but for a year I get 40$ tun adjustments. Maybe it’s worth just sending it back with more info, but I’d think the hardware that records data for their fine tuning would be a better way than trying to relay instruction. I’m still unsure of the fact that my injectors have zero seal at the intake port. New orings didn’t solve that. They just sit in there with no detent action. Do they solely rely on the “clamping” force allied by bolting down the rail?
There aren't any recesses for the o rings in either than manifold or the rail. The rail clips hold the injectors in their orientation in the fuel rail. Fuel pressure will work to push the injectors into the manifold and manifold vacuum will work to pull them into the manifold. The clips keeps them immobile and the o rings just seal against the pressure. The injectors fully inserted were pretty firm in my manifold though. My injectors were hard to get out because of the thick black paint the entire manifold was coated with which by research was a Mercruiser marine anti-corrosion treatment. It was obviously done after assembly because the entire manifold was coated including the injectors and MAP sensor so I had to break the paint to extract the injectors. There was a small amount of rust binding some which Evaporust took care of. Two of the injectors left their crowns in the manifold they were held so tight so I had to use a pick to get them out. By description and the pictures on this thread your manifold is the same as mine and slightly different than the OPs. The PPED write-up noted a red painted upper like the OPs and mine was black same as yours. Also the OPs thermostat housing is two bolts clocked for the pre-96 water neck which I now see why the PPED write-up mentioned needing to use a pre-96 water neck and upper radiator hose. Mine and yours had a 4 bolt marine thermostat allowing the clocking of a water neck such that either the Vortec original or the pre-96 could be used.
 

L31MaxExpress

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There aren't any recesses for the o rings in either than manifold or the rail. The rail clips hold the injectors in their orientation in the fuel rail. Fuel pressure will work to push the injectors into the manifold and manifold vacuum will work to pull them into the manifold. The clips keeps them immobile and the o rings just seal against the pressure. The injectors fully inserted were pretty firm in my manifold though. My injectors were hard to get out because of the thick black paint the entire manifold was coated with which by research was a Mercruiser marine anti-corrosion treatment. It was obviously done after assembly because the entire manifold was coated including the injectors and MAP sensor so I had to break the paint to extract the injectors. There was a small amount of rust binding some which Evaporust took care of. Two of the injectors left their crowns in the manifold they were held so tight so I had to use a pick to get them out. By description and the pictures on this thread your manifold is the same as mine and slightly different than the OPs. The PPED write-up noted a red painted upper like the OPs and mine was black same as yours. Also the OPs thermostat housing is two bolts clocked for the pre-96 water neck which I now see why the PPED write-up mentioned needing to use a pre-96 water neck and upper radiator hose. Mine and yours had a 4 bolt marine thermostat allowing the clocking of a water neck such that either the Vortec original or the pre-96 could be used.
My manifold is a Mercruiser, I painted the upper red.

Mine has the stock L31 thermostat housing. A 92 Caprice thermostat housing works on the manifolds that only have 2 bolt holes.
 
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JeremyNH

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My manifold is a Mercruiser, I painted the upper red.
Understood but your manifold also only has two bolts for a thermostat housing and mine and Singlecabs have 4. Upper manifolds look to be the same but the lower are different. Mercruiser obviously did a modification at some point. My manifold comes off a 2005 with a 305.
 

L31MaxExpress

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Understood but your manifold also only has two bolts for a thermostat housing and mine and Singlecabs have 4. Upper manifolds look to be the same but the lower are different. Mercruiser obviously did a modification at some point. My manifold comes off a 2005 with a 305.
Mine has 4 bolt holes at the water neck. Mine is off a similar era 6.2L. It had the external remote mounted Ford IAC.
 

L31MaxExpress

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The other manifold I had was off a newer 305. It was a 4 bolt plenum. Used a LS 4 to 3 bolt adapter to bolt a 3 bolt throttle body right on to it. The 4 bolt plenum is easy to use, I do not know why some claim they will not work. Cheap adapter plate and send it.
 
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