block rust

[NexiusEvaro]

hey all

found this unsettling bit of business last night...

I tried to post the pics in thread, but my free webhost is blocking direct links now... so they are attached.

I bought this block/trans as rebuilt and never fired. The head was done by a shop and I am told it has oem fasteners and oem HG. I was told it should be good to 300-350 HP. Simply trying to do a more or less stock turbo swap on an NA. In preparation, I have been taking off components, cleaning, replacing, repainting etc... and hadn't noticed this mess until last evening.

What do you guys think? Is this surface rust from sitting in humidity for too long since the rebuild or maybe residual damage caused a long time ago initially by a bad HG?

If the damage is not a potential timebomb, how does one go about cleaning the rust off a junction like this without damaging the HG? I have been trying to decide if I want to push things back several months and several $$'s and tear the head off and put proper fasteners/HG... does this clinch it?

thanks

nex

 

[Clip]

to me most of it looks like surface rust, except for the few spots along the seams. i'd tear it all down, though, just to be safe. looks nothin like the rust i've been dealing with on my truck.

 

[lagged]

its cast iron thats just how it is.

clean it up with a wire brush or some sand paper and paint it over.

 

[Clip]

if you're really concerned you could break out the bristle wheel for a drill and clean it up. either that or could you use naval jelly on it to convert it to primer, then paint?

 

[NexiusEvaro]

if you're really concerned you could break out the bristle wheel for a drill and clean it up. either that or could you use naval jelly on it to convert it to primer, then paint?

I was planning on scrubbin it with a small brush and dremel then repainting... if that's not gonna screw up the HG seal...

How does the naval jelly work? you just rub it on until the rust comes off or is chemically altered then paint over it?

Seems like a good approach but i dont know much about it... so far I have just been cleaning (brush, sandpaper, dremel with brass rasp attachment) and repainting the cast iron parts... here's a pic of the supra "parts art gallery" attached. (ahh, you just gotta love the bauhaus take on aesthetics...)

appreciate yer input

nex

 

[Clip]

my guess is that it chemically alters the iron oxide to form some sort of primer that readily accepts paint. my dad spent a few nights in the shop working on an old plow for the antique tractor with that stuff, cleaned it right up.

 

[NexiusEvaro]

dunno

looks like its a viscous phosporic acid - its water soluble tho so you can rinise it off...

still i wonder if you want to be doing that to the edge of the HG and head...

here's a stat sheet from a chemical company on it

http://www.shorechemical.com/Section 7 Tech Sheets/naval_jelly.htm

nex

 

[suprageezer]

To remove rust I use what’s commonly called Wood Bleach, Oxalic Acid. Some pharmacies carry it. It's cheap and won't harm anything except Rust. DuPont used to have it in their Radiator cleaner (the only brand that ever actually removed rust) not sure if they still sell it. As far as cast iron rust, it's totally just surface rust; it would take a zillion years for a cast iron block to turn to a pile of rust dust.

 

[IJ.]

Outside no biggie it's just an annoyance but I'd be very concerned at the Bore condition.

If it got plenty of good assembly lube when it was built it'll be fine if not you could have a problem

 

[NexiusEvaro]

Outside no biggie it's just an annoyance but I'd be very concerned at the Bore condition.

If it got plenty of good assembly lube when it was built it'll be fine if not you could have a problem

understood.

Is it possible to verify bore condition with a scope or a similar tool or is it necessary to pull the head? I have turned the motor over with a ratchet to check TDS and reinstall the CPS. It took a small amount of extra force to get it to turn at first and was very smooth therafter. I did hear some clicks etc as I rotated the crank, but I don't have the chops to know what I was listening to well enough to know if it was normal or not...

Appreciate the input IJ and thanks for the tip suprageezer, I will look into it...

regards

nex

 

[IJ.]

Scoping it BEFORE turning would have been better but yep you can have a look if you have access to a scope just for peace of mind!

 

[NexiusEvaro]

yep...

another lesson learned - I will run down a scope and have a look an try to post a pic of the block after clean up if things look rust free inside

thx

nex

 

[NexiusEvaro]

hey guys

progress shot of the block rust clean up - seems to be coming off fairly easy so far... still havent decided what to put on it.. tape/bag it and spray it with engine paint or find some kind of epoxy clear coat or something that I can brush on for some protection... really kind of like the raw metal look, actually...

Anyway, I cleaned up the crank pully and it turned out pretty good. pic attached below... I am wondering if anyone has any good ideas on how to keep it looking like this...? clear coat it or leave it alone? Figured that exposed metal would rust up very fast... don't really know.. is it better to always coat exposed metal with something or clean off the rust and just leave it ?

/endnewbism [heh, god i wish....]

thx

nex

 

[jdub]

It will rust...fairly quickly too. I'd just use black engine paint.

 

[suprageezer]

Or use Red Insulating Enamel to get a good long term seal on the cast iron, inside the enigne and out. Then paint it what ever color you like over that. I use it around any water inlets or outlets, on aluminum too.

 

[NexiusEvaro]

thx info jdub

ok to paint the whole pulley... or should i avoid painting the belt tracks (does it cause slippage at all?)


is this the correct paint suprageezer?

http://rshughes.com/catalog/121010.html

regards

nex

 

[jdub]

You can paint the whole thing...the belts will wear the paint away and keep rust from forming.