Repainting rusted headers??

[BMXER10]

The headers on my Kubota is getting rusted badly over the years. I tapped on it with a hammer lightly and its definitely not anywhere close to rusting through. But im concerned because the rust is causing the bolts that attach it to the block to rust. Its only about $30 for new bolts and gaskets so Im going to order them up.

My question is should I be careful removing the old bolts? Any specials precautions? I dont want to break a bolt in the block.

Are high temp paints that come in a can any good? I imagine I would need to get the header sand blasted to remove the old rust.

Everything else under the hood is in excellent shape.

 

[Patches]

I use "VHT" brand,available at most specialty speed shops. You must remove all the current rust possible, and it will take multiple "coats", as there is very little pigment in the coating,compared to most other high temp. paint, but you'll be happy with the results and it wears well, if your equipment is kept under cover. I've used it on my wood burning stove also, and have had that much hotter than a diesel exhaust manifold. No burn off or flaking

 

[john_bud]

Is the oil filter really 3 years and 4 months old? Might be time to change.....

If you go to a commercial paint store where they mix and sell automotive paint, you can get them to mix up some high temp paint. Have them do it for brushing. Different solvent mix. Or you can go to Eastwoods site and get high temp brushable. I've used the stainless paint and it's pretty good, but you HAVE to thin it down and use many coats or it will not stick.

You do need to get it clean. Sand blast is best. Harbor freight sells a needle descaler that works pretty good. Or a wire brush 4" or 5" in an angle grinder. Get all the oil off then coat.

 

[Wayne County Hose]

I would send it out and have it ceramic coated, like they do with automotive headers. You take it off, send it out, and you never have to touch it again. If memory serves me correctly, there is a company in Connecticut called Jet Hot that does a great job.

I would be careful removing the old bolts, but I just changed the exhaust manifold on my 1950 Allis-Chalmers. Some of the bolts were a pain, but they all came out.

 

[Skerby]

i would leave it alone, aint worth the money, just cosmetic.. if that's not an option "I" would see if the new paint that converts rust to a solid and halts further corrosion is a high temp cover or not.. i'm not sure if it's 3m or rustoleum who makes it.. it that isn't a good choice i'll simply leave the header ON if the bolts, after wd40'ing them over a few hours, didn't loosen them up, and then wire brush as much as i could reach maybe portable sandblaster too and cover adjacent material w/ cardboard, then shoot them with a high temp aerosol can from walmart's auto section.. good luck.

 

[Scooby074]

Sand blast it. Wash with lacquer thinner. Then pain with por-15 manifold paint. High Temperature Paints-POR-15 Inc. or use the VHT paint Patches recommends, both are good products.

 

[BMXER10]

Is the oil filter really 3 years and 4 months old? Might be time to change.....

Thats an old pic actually... I changed the filter recently.

 

[Skerby]

after thinking about it here's what you should really do.
remove the exhaust manifold, send it out to be scanned so a new one can be
manufactured in heat resistant composite materials using the latest nanotechnology built up molecule by molecule, then have it sent to eqypt to be rightfully encrusted with jewels from the tombs of such great gods as isis and osiris, returned to have the remaining exposed composites garnished with gold electroplating and finally installed back on your kubota for future generations to behold, entrusting it upon your demise to the great institution which is the smithsonian.... good luck with that.

 

[Eagleview]

Why would you bother ? They are cast iron not steel . It will out live you the way they are . I have never in my days seen a cast iron manifold rust through .

 

[Skyco]

I've never seen one rust through either but I did have one that rusted enough to leak where it sealed to the head. The factory method had no gasket, direct metal to metal which worked for 10 years until it started leaking. When I removed it the formerly machined sealing surface was all rusted up enough to leak, fortunately it rusted before the head. Bought a new manifold and a metal gasket designed to reseal to a used head, fixed it right up. This was on my 96 Powerstroke 7.3 in a F350.

 

[crashz]

Since its not leaking, I'd leave it alone. If you are worried about future service and breaking bolts, you could put studs in place, but its a lot of work for marginal benefit.

For purely cosmetic solutions, why not try the cast iron manifold paste that is found in common restoration catalogs (LMC, JC Whitney, Summit, etc)? It is a paste that brings back the original finish of the cast. A quick spray of high temp clear, and it should last a long time and look good doing it.

 

[mrutkaus]

Yes I'd be very careful with the bolts, keeping them soaked for as long as you can with PB blaster, wd40 etc before you start on them. Then if there is any chance of breakage, ie tight, spray several times during removal.

When I removed some bolts from a Mercedes engine block, I built a well out of clay and a drip tube and soaked the bolts for a month or more before I started working on them.

Mike

 

[flusher]

The headers on my Kubota is getting rusted badly over the years. I tapped on it with a hammer lightly and its definitely not anywhere close to rusting through. But im concerned because the rust is causing the bolts that attach it to the block to rust. Its only about $30 for new bolts and gaskets so Im going to order them up.

My question is should I be careful removing the old bolts? Any specials precautions? I dont want to break a bolt in the block.

Are high temp paints that come in a can any good? I imagine I would need to get the header sand blasted to remove the old rust.

Everything else under the hood is in excellent shape.

Use a rust converter like Orthophos on the rust (wire brush the loose stuff, but don't remove any of the other rust) and then a high temp paint. The cheapest stuff is the black paint for barbeques.

 

[ampsucker]

since everybody has an opinion on this, i'll add mine! ;-)

agreed that cast iron manifolds rarely rust through. the most common problem is cracking - usually due to something cold like a/c condensate dripping on a hot manifold. not going to be a problem for you. if you don't have any leakage or warpage, it's unlikely the mating surface is going to corrode as it's very much insulated from oxygen penetration due to the compression of the seal between the metal parts.

if you just want to make it look better, paint it. although i've had mixed results with "high" temp paint from a can. never tried the high dollar stuff from a custom mix, though. having it powder coated or ceramic coated would most likely last longer. usually, that type of "send out" stuff is done for the insulative effect of retaining exhaust gas speed and heat out through the tailpipe in performance auto applications. it's not going to help your tractor perform any better but will probably last longer cosmetically than paint.

if you just want to make sure you can service it later, take each bolt out one at a time after soaking with penetrating oil, coat with anti-seize lube, and reinstall. make sure you torque to proper spec with a good torque wrench. that will insure an even seal where the manifold meets the block.

amp

 

[RWolf]

There is another way to remove rust from your exhaust manifold without sending it out to be sandblasted and you can do it a home fairly easy. The diagram is pretty straight forward. Use a clean piece of steel for the positive plate, Your manifold for the negative and a "trickle" charger for the power source. The liquid is a 10% solution of washing soda (sodium carbonate, soda ash) and it is available at many grocery stores in the laundry detergent aisle.

forgot to mention this process will take about 48 hours but is entirely hands off. After cleaning then a coat of barbacue paint or other high temp. paint of your favorite color.