Filling the Oil holes in a 3L Hybrid, with what?

What is everyone using to fill the oil return holes in their 3L shortblock in prep for the 2.5L heads? JBWeld?

Originally posted by rkneeshaw:
What is everyone using to fill the oil return holes in their 3L shortblock in prep for the 2.5L heads? JBWeld?

I only used JB weld,Ive heard of quicksteel being used also.

i used the jb weld putty first then topped it off with the jb weld that comes in the 2 tubes!

in the return holes I lined it with a little bit of jb weld, filled in with quicksteel. On the oil feed, lined it with jb weld and used an allen head plug.

what size plug?

I'd go with quicksteel.

Filling the oil return holes...

Originally posted by DemonSVT:
Filling the oil return holes...

The man is right. Oval ports own.

But if you have to fill em Trident should do the trick.

I drilled a hole and tapped it then put a bolt threw the side then put JB weld in it.

Weld it over to seal the holes, then re-deck the block. Only way to go. I wouldn't trust JB Weld as far as I can chuck the 3L with my bare hands.

Same with the rear head front oil supply hole. Only way to guarantee you'll never have any problems.

Overkill? Perhaps... Did it on mine, and on Pete's hybrid. Only way I'll do hybrid builds, since I have an "in" with a welder who is a true artist.

Why re-deck the block? Those three holes aren't covered by the heads at all (hence the need to fill them), right?

they are covered by the heads, but the heads do not have the corresponding holes. And Dan has the deck redecked, because he has his welded, so he makes sure the mating surface is still flat.

You have to remember that redecking the block lessens the piston to valve clearance and it's very close to the bare minimum as is.
(Safe limit for deck or head milling is a combined total of .006" )

Also compression is raised slightly which on a hybrid is starting to play with fire if both quality octane fuel and custom chip tuning are not available. (around .2 or maybe .3 more CR for removing the limit)

My advice (if you really want to lose them by running a hybrid

) is to tap the holes and plug them with a hex plug. Loctite or JB weld on the threads.

I mis-spoke. Instead of actually "decking" the block again to bring it all even, the shop took a machine file to the area and took the fill-in areas down to deck height. The entire surface was not ground down, only the fill spots, then measured with a gauge to determine tolerance.

A re-decking involves disassembling the entire block- This machining was done with the shortblock still assembled, and the rest of the ports sealed with tape to avoid contamination.

Originally posted by DemonSVT:
My advice (if you really want to lose them by running a hybrid ) is to tap the holes and plug them with a hex plug. Loctite or JB weld on the threads.

Its funny how you bash hybrids now, and if I pull up some posts from 2yrs ago they were the best combo to run, even though the oval ports were around then as well

Originally posted by kinger:

Originally posted by DemonSVT:
My advice (if you really want to lose them by running a hybrid ) is to tap the holes and plug them with a hex plug. Loctite or JB weld on the threads.

Its funny how you bash hybrids now, and if I pull up some posts from 2yrs ago they were the best combo to run, even though the oval ports were around then as well

Well, I remember a year ago when hybrids were all the rage. But now that I have learned more, I'd likely go full 3L just because of the oiling issues.

While we're on this subject, is it realistic to think I could put the SVT cams onto the 3L head & get the benefits of both the larger valves & the longer duration of the cams? I'm guessing not, since everybody is swapping out heads & going through the bother of oil return hole issues & such.

Originally posted by kinger:
Its funny how you bash hybrids now, and if I pull up some posts from 2yrs ago they were the best combo to run, even though the oval ports were around then as well

Yes but 2-3 years ago I had not personally done all that extended high rpm testing either. (nor had the flow data on stock oval port heads!)

My original thinking was the hybrid's extra CR would be ideal to take advantage of a very high redline. That has obviously changed with all the data I have collected!

Also all the oiling information I have collected points to BADLY NEEDING the extra drains the 2.5L block does not have. That in itself it more than reason enough to not run a hybrid when upgrading to a 3L.

Hard data has shown that higher compression and higher rpm is not remotely worth it at all.
For instance MBT timing can be used with a normal compression ratio unlike a hybrid. MBT timing will produce the best overall power numbers every time.

Then there is the fact the stock tumble port (oval) heads out flow or equal well ported split ports. (which is the opposite of the manifolds btw)
Plus they are about $1000 cheaper verses paying for port work and valve installation!!! That's $1000 that can be much better spent elsewhere.

Even the basic oval port builds match the good hybrid builds which is just another thing showing a hybrid is not the right choice to make.

I noticed QuickSteel has a maximum temp of 300 degrees F, and the two tube kind of JB Weld has a max temp of 600 degrees F. Anyone had any issues with QuickSteel on an engine block getting too hot?

I figure I'll be safe with the JBWeld, but someone might not notice that the putty version of JBWeld is also only good to 300 degrees like the quicksteel, you have to get the kind of JB Weld that comes in two tubes and you mix to be safe to 600 degrees.

Originally posted by rkneeshaw:
I noticed QuickSteel has a maximum temp of 300 degrees F, and the two tube kind of JB Weld has a max temp of 600 degrees F. Anyone had any issues with QuickSteel on an engine block getting too hot?

I figure I'll be safe with the JBWeld, but someone might not notice that the putty version of JBWeld is also only good to 300 degrees like the quicksteel, you have to get the kind of JB Weld that comes in two tubes and you mix to be safe to 600 degrees.

about 10K on my 3L

used jb weld putty then jb weld tubes on top of it, still holding fine!

Originally posted by TourDeForce:
While we're on this subject, is it realistic to think I could put the SVT cams onto the 3L head & get the benefits of both the larger valves & the longer duration of the cams?

I think so. Isn't this what Demon's running?

Originally posted by DanG:
I mis-spoke. Instead of actually "decking" the block again to bring it all even, the shop took a machine file to the area and took the fill-in areas down to deck height. The entire surface was not ground down, only the fill spots, then measured with a gauge to determine tolerance.

Welding to seal the extra vents is not a good idea. You can warp the block deck surface. Just because the machine ship went only "down to deck height" does not mean the "wavy" warped deck doesn't still have some low spots that can mean a future blown head gasket.

JB weld or quicksteel works fine. JB Weld will ooze more, so I installed it, taped over it and rotated the engine stand 180 degrees so that gravity worked with me, not against. I removed the tape and it was rock solid and has held up just fine.

Originally posted by DemonSVT:
My advice (if you really want to lose them by running a hybrid ) is to tap the holes and plug them with a hex plug. Loctite or JB weld on the threads.

If only that would work. Any hex plug large enough to seal the oil return holes would need to be drilled into the water jacket next to it = no worky. You could try to drill two small ones side by side into the rear edge of the block, but then you'd still need to lay some type of epoxy over them from the top side to seal it off.