What advantages are there to painting the inside of the block?

[gagembassett]

Gentlemen,

For those who have & still do paint their blocks with glyptal. I once heard someone say that they use a handheld propane torch & paint thinner. They wipe they paint thinner on & use a torch to cook off the oil, said they repeat that process about 7 or 8 times minimum before they paint the block to ensure it is good for best glyptal results.

What's everyone's thoughts?

 

[Demonracer]

I have the inside of my 408 coated with Glyptal. When I sent the block to the machine shop, my machinist suggested it. He baked the block to burn out the oil in the porousity of the block and I took it home to paint it before the machine was done. That was 15 years ago and it still looks good. I can't say how much it affects the oil drain back, but it may help with it.

 

[go-fish]

I have a virgin 5.9L block that is NOS from Mopar Performance. I thought about doing the Glyptal coating because the only oil the block has ever seen is for storage and corrosion resistance. Moreover, I was thinking about getting the block stress relieved in an oven. If my new machinist has the equipment I would get it stress relieved and paint glyptal.

@Demonracer actually answered a question that I had; Will baking a used block be enough heat to effectively make enough oil leach from the cast? Sounds like it. Off topic thought now is, would a virgin block NEED to even be stress relieved for a 5-700 horsepower engine build?.

Would Glyptal adhere just fine if I did the torch and paint thinner method? Can the outside of the block accept Glyptal?

 

[harrisonm]

Glyptal coating. when the block is clean and dry. Helps the block from retaining oil and any break in particles from sticking. Oil flows to the sump faster. Steve has customers that request it at the machine shop. Usually done before machine work . Block must be spotless and dry

View attachment 1716438022

View attachment 1716438023

View attachment 1716438024

View attachment 1716438025

View attachment 1716438026

View attachment 1716438027

View attachment 1716438028

I totally agree with the fact that the inside of the block must be dry and clean. But how do you clean the inside of a block that has been soaking in oil for 50 years?

 

[MrCab]

I totally agree with the fact that the inside of the block must be dry and clean. But how do you clean the inside of a block that has been soaking in oil for 50 years?

I've painted the insides many Mopar motors with Rustoleum damp proof red primer and or Glyptal after having them hot tank after all the machine work was done, I use both Shell Solve 360 cleaning solvent (or its equalivent(SP?) of another brand and then cans of a good brand of spray brake cleaner that doesn't leave a residue to make sure they are really clean
I do use a propane torch to make sure any engine block part, lifter valley that I'm going to paint and seal is dry before I start. I need to hold the flame on a spot until I see the water boil out and then move on until the entire lifter valley is completely dry
I started doing that a long, long time ago (30+ yrs ago) with no come backs or failures that I am aware of
I do deburr all the blocks I build before starting on them to build so getting them clean is #1 on my to do list before starting the assembling of them, the quicker oil return on any engine using a stock 4 or 5 quart oil pan can't hurt Engine assembling is a lot like brain surgery, you can NOT keep it to CLEAN

 

[famous bob]

If paint ever emulsifies with detergent oil you could have issues from bearing wear to clogged oil passages. IMO no way is it worth doing. But WDIK?

To me is : do the prostock engine builders do it ??!!

 

[gagembassett]

I just did the full inside of my 360 block with red glyptal. My impression is, you ever tried to slide barefoot across course concrete vs. polished concrete? I would think oil likes to slide down a slicker surface. Just my two cents but to each their own. Do the proper prep work like I did (wipe down the inside with acetone on a cloth then use a handheld torch to help cook oil out of the pores) & I would see no problem of it flaking off.

 

[MrCab]

We will probably never know what Pro Stock engine builders due, will we

 

[MOPARMAGA]

Glyptal will wash off with hot water .
That's just a fun fact.

 

[MrCab]

Glyptal will wash off with hot water .
That's just a fun fact.

You're the first one I have heard that from

 

[MOPARMAGA]

You're the first one I have heard that from

Well to be fair, soaked in a hot detergent tank.

 

[gagembassett]

Glyptal will wash off with hot water .
That's just a fun fact.

Now that's just a lie. It's an ally enamel that stands up to parts washers even. Hot water may slightly wash it off when it's still wet but it's not going to make the stuff even sweat once it's cured

 

[gagembassett]

Well to be fair, soaked in a hot detergent tank.

I commented before your 2nd reply

 

[RAT ROD AL]

 

[Killer6]

And when it comes to all-out class drag racing that mandate a stock/stock type pan,....they don't want the oil getting back to the pan,....they put just enough oil in it to make it thru' the traps, then shut it down, the higher the revs....the more it's worth.

 

[MOPARMAGA]

I commented before your 2nd reply

I was surprised, it washed right out of my block.
So I never put it back in.

 

[RustyRatRod]

I'm not sure I'd do it on a block that's been run. Cast iron by nature is porous. There's no way you'll ever get every bit of oil off. I'm not sure it really makes a difference anyway, unless you just like the look.

 

[dirty white boy]

i know rockwell and etan-fuller both do it to inside of heavy duty truck rear ends and transmissions! never seen CAT or cummins or driptroit do any thinq on inside of enqines expected to live a million miles pullin 80,000+ lbs!!

 

[MOPARMAGA]

I'm not sure I'd do it on a block that's been run. Cast iron by nature is porous. There's no way you'll ever get every bit of oil off. I'm not sure it really makes a difference anyway, unless you just like the look.

It's done on a block that's been run 99% of the time

 

[Ottmundr]

Very pretty, but I wouldn't do it.
Remember whose name is on the title.
If someone wants to paint the inside of their block, that's great. We can all learn from the experience.

 

[9secRR]

never done it and never will. don't see any reason to. waste of money and time.

 

[MOPARMAGA]

never done it and never will. don't see any reason to. waste of money and time.

I just noticed you joined fabo 1 year before my sobriety date lol

 

[Icetech]

Soo... doing my current motor, i actually have a 40+ year old can of glyptal and was going to do it.. torched the block like 3 times to make sure it was clean, then didn't do it. The thing about sliding easier on the paint is obviously true, but after there is a wet coat of oil on the valley walls wouldn't it basically make anymore more oil slide just as easy? You are giving up a tiny bit to coat the surface at the start.. but if that much is going to be an issue.. you need more oil anyway

P.S. the main reason i decided not to do mine is, just a street beater motor... so not really needed

 

[toolmanmike]

I wouldn't paint the inside. Too much risk of it flaking off. Oil will drain back into the pan with or without the paint. OK, may be it will drain back faster with the paint but is it worth the risk? Isn't that what deep pans are for? (to make sure there is plenty of oil for the pump to pick up)

 

[MrCab]

I wouldn't paint the inside. Too much risk of it flaking off. Oil will drain back into the pan with or without the paint. OK, may be it will drain back faster with the paint but is it worth the risk? Isn't that what deep pans are for? (to make sure there is plenty of oil for the pump to pick up)

Two reasons to paint the inside of the blocks, especially BB Mopars if you have used a grinder to deburr the casting flashes inside those blocks. The paint will seal the pores and trap the microscopic pieces that were ground off and imbedded in the block. The second thing is for oil return, especially on any motor using a stock small capacity pan like most small blocks and a lot of the pre 1967 BB. or any motor that has 4 quarts and is drag race and revved above 5000 RPM. I like using the 1970/1971 stock Mopar 6 pack and street hemi oil pans, they hold 6 quarts in the pan and, depending on which oil filter you're using whatever amount of oil it will hold. On BB you can drill all the small depressions in the lifter valley where oil will pool to make sure most of the oil drains back into the oil pan, I'm not talking about half a pint or more, I'm talking about maybe 3 to 6 ounces at the most but every drop in the oil pan is available to be used for lubricating