Fan housing, What’s the best way to clean and paint one. Options

[jsaum]

I’m disassembling a 1.7 parts car engine and want to paint the fan housing for a future engine build. After a couple of hours of scrubbing and cleaning I can see metal underneath all of the caked on grease and oil! What’s the best next step cleaning and prepping process before paint? Is oven cleaner ok to use?

Thanks,
Jsaum

[914_7T3]

Have it tumble blasted, but do not paint. Anything that will inhibit heat dissipation should be avoided on air-cooled motors.

This one was tumble blasted and has returned to its original magnesium finish to tarnish again over time.

[bbrock]

Have it tumble blasted, but do not paint. Anything that will inhibit heat dissipation should be avoided on air-cooled motors.

This one was tumble blasted and has returned to its original magnesium finish to tarnish again over time.

Now I've learned something new today. Had to Google that one. Can you explain the benefit of tumble blasting as opposed to something like walnut blasting?

[914_7T3]

Have it tumble blasted, but do not paint. Anything that will inhibit heat dissipation should be avoided on air-cooled motors.

This one was tumble blasted and has returned to its original magnesium finish to tarnish again over time.

Now I've learned something new today. Had to Google that one. Can you explain the benefit of tumble blasting as opposed to something like walnut blasting?

As per one of the tumbler manufacturer's website, "In tumble-blast batch processing machines, all surfaces of components are exposed to impact treatment as the parts gently turn over and over in a slowly rotating tilted basket.
This design virtually eliminates component damage due to part-on-part impingement that is so common with “barrel-blast” machines. Our tilted basket generates greater circulation of components in the batch, which not only yields more thorough and uniform coverage, but also makes for a shorter blast cycle – typically five minutes or less!"

My local supplier did not disclose the type of media used, however upon completion of the process, the pores of the magnesium are left closed. No need to seal it with clear or paint.

[URY914]

Easy-Off Oven Cleaner works well. And don't paint it.

[jsaum]

Have it tumble blasted, but do not paint. Anything that will inhibit heat dissipation should be avoided on air-cooled motors.

This one was tumble blasted and has returned to its original magnesium finish to tarnish again over time.

That looks great.

[rstover]

It is my understanding that cerakote will no hinder heat dissipation. This is a picture of one that I had cerakoted. I don't remember the color.

[mepstein]

Cerikote is good stuff. I’m not sure the fan housing gets hot. Isn’t it’s purpose to bring in fresh air? If so, it shouldn’t be getting hot.

[rstover]

Cerikote is good stuff. I’m not sure the fan housing gets hot. Isn’t it’s purpose to bring in fresh air? If so, it shouldn’t be getting hot.

Some had mentioned not to paint or powder coat because heat would not dissipate. The cerakote to me is a good option. I believe there are many applications where cerakote is a very good option. I was shown the booth where he applied it and it had some serious fan and filter, it must be very toxic to apply.

[mepstein]

Cerikote is good stuff. I’m not sure the fan housing gets hot. Isn’t it’s purpose to bring in fresh air? If so, it shouldn’t be getting hot.

Some had mentioned not to paint or powder coat because heat would not dissipate. The cerakote to me is a good option. I believe there are many applications where cerakote is a very good option. I was shown the booth where he applied it and it had some serious fan and filter, it must be very toxic to apply.

Yes, you need a good respirator.

[jsaum]

Cerikote is good stuff. I’m not sure the fan housing gets hot. Isn’t it’s purpose to bring in fresh air? If so, it shouldn’t be getting hot.

Some had mentioned not to paint or powder coat because heat would not dissipate. The cerakote to me is a good option. I believe there are many applications where cerakote is a very good option. I was shown the booth where he applied it and it had some serious fan and filter, it must be very toxic to apply.

Yes, you need a good respirator.

I googled it and found a shop a few miles away from me. I’ll give them a call and see how much they charge.

[IronHillRestorations]

It's an impeller (fan) housing and IMHO heat dissipation isn't a critical concern.

I've media blasted and painted several without a discernible change in engine temps.

[DRPHIL914]

It's an impeller (fan) housing and IMHO heat dissipation isn't a critical concern.

I've media blasted and painted several without a discernible change in engine temps.

I agree, I have seen no increase in temp issue with my newly powdercoated fan housing, but powdercoating is thick and may effect the continuity of the ground for the alternator( I am having this issue) But temps are not an issue(oil or head temps)

Phil

[mepstein]

It's an impeller (fan) housing and IMHO heat dissipation isn't a critical concern.

I've media blasted and painted several without a discernible change in engine temps.

That's what I thought. Mag is a pretty reactive metal and I wonder if paining actually increases its lifespan by slowing down corrosion.

[dr914@autoatlanta.com]

totally agree no paint, will flake off after a while and look like crap. Also Porsche painted the sheetmetal black to dissipate the heat better than any other color


quote name='914_7T3' date='Nov 24 2018, 06:00 PM' post='2668357']
Have it tumble blasted, but do not paint. Anything that will inhibit heat dissipation should be avoided on air-cooled motors.

This one was tumble blasted and has returned to its original magnesium finish to tarnish again over time.




[/quote]

[914werke]

It's an impeller (fan) housing and IMHO heat dissipation isn't a critical concern.

I've media blasted and painted several without a discernible change in engine temps.

(IMG:style_emoticons/default/agree.gif) James do whatever will protect it.

If you want to shortcut the process I have both early & late housing already finished.

BTW the Impeller housing was never bare as delivered. It WAS covered with some coating that gave it a slight iridescent gold color from the factory

[mepstein]

It's an impeller (fan) housing and IMHO heat dissipation isn't a critical concern.

I've media blasted and painted several without a discernible change in engine temps.

(IMG:style_emoticons/default/agree.gif) James do whatever will protect it.

If you want to shortcut the process I have both early & late housing already finished.

BTW the Impeller housing was never bare as delivered. It WAS covered with some coating that gave it a slight iridescent gold color from the factory

Probably the same as the trans.

[914_teener]

It's an impeller (fan) housing and IMHO heat dissipation isn't a critical concern.

I've media blasted and painted several without a discernible change in engine temps.

(IMG:style_emoticons/default/agree.gif) James do whatever will protect it.

If you want to shortcut the process I have both early & late housing already finished.

BTW the Impeller housing was never bare as delivered. It WAS covered with some coating that gave it a slight iridescent gold color from the factory

Probably the same as the trans.

Yep.

Probably some type of conversion coating that was found later to be environmentally un friendly later on. Only a quess.

I know enough about metallurgy to be dangerous.

[IronHillRestorations]

I've used clear engine paint, and a Dupli-Color cast metal paint with good results. I like powder coating, but getting a jobber that can do quality work with a detailed cast alloy part like this would be the key.

Any coating can come off over time. It's usually the next 5-10 years that matter.

If I went through the trouble and expense of getting one all cleaned up and tumble blasted or whatever, I'd put a protective coating on it. The magnesium alloy should be protected, IMHO.

I think the factory used some type of Cosmoline like coating, but I've been wrong many times before.

[bbrock]

I think the factory used some type of Cosmoline like coating, but I've been wrong many times before.

I don't know why, but I researched this when I started my resto. The stuff they used was Tectyl 846 which pretty much looks like Cosmoline to me. Like Cosmoline, I expect it to melt off and be gone in the first couple hundred miles. I think it was intended pretty much just to protect during shipping. Here's what it looks like on my block.

(IMG:http://www.914world.com/bbs2/uploads/post-20845-1492440261.jpg)