Jump to content

Advice for spraying Engine enamel with HVLP gun


special55

Recommended Posts

Guest buicks39

is the engine in or out of the car? i have never myself used a gun,only rattle cans and they look good.how ever i do know people who do use a small detail gun.make sure all the grease is off and use a high heat primer.

Link to comment
Share on other sites

Hey 39,

Engine is out and just went through a fresh rebuild. The block was sent out and cleaned and all the sheetmetal parts blasted and primed. I just need to give it a final once over and start sprayin

I just wanted to seek a little advice from those that have been there and done that.

Rich

Link to comment
Share on other sites

You need to familiarize yourself with spraying with a gun. Hiopefully it is a small touchup type. A fullsize spraygun is kind of over kill with an engine. If you call Bill Hirsch, he can give you the proper amount to thin the paint and what you should use as thinner. A quart of paint is way plenty to paint an engine and should give you enough to do a little practicing before you paint the engine. Make sure that you wipe the area to be painted with a degreaser or alchol to make absolutely sure there is no contamination on th engine. Take your time.

Link to comment
Share on other sites

Thanks for the response guys,

I did contact Bill Hirsch and they were able to tell me what to thin with but were no help on what size tip to use if spraying unthinned which is my first preference.

I am familiar with syphon feed guns but this is my first go around with the HVLP. I will take your advise and spend a little time spraying some scrap to get the feel.

Any more advise out there guys?

Keep it coming

Rich

Link to comment
Share on other sites

Either an enamel or lacquer reducer will work fine. You Don't need a "special" reducer. A slow (or hot weather) reducer is recommended because the paint sets up fairly quickly and you want it to have time to flow out.

What I do is use a disposible bristle brush on the block and any cast iron to apply two coats, unthinned. By the time I finish with the first coat it's time to do the second. For any smooth parts I prime with a self etching primer. I thin the paint to a normal consistancy and apply two coats. I apply the second coat when the first has set up to a tack. I sometimes will even apply a third coat if I want a really nice finish such as on valve covers. BTW, if you have small dings in valve covers or air cleaners regular polyester body filler will work just fine to level them out.

This works very well and lasts a long time..............Bob

Link to comment
Share on other sites

Don't let the HVLP mess with you. It will operate very similar to your older siphon gun. Before you mix your paint be sure to have a plan on where your gun can be placed for filling and between coats. A wire gun stand is best but just give it some forethought. You do NOT want to get the cup full of paint with no where to go with it.

An order to get engine enamel to spray you may have to up your pressure at the gun. This will reduce the benefit of the HVLP any way. The HVLP is a bigger factor for a production paint shop meeting EPA standards. The few times you will most likely paint are not what is being monitored.

Good luck

Link to comment
Share on other sites

I paint before assembly so everything is painted seperately. When I spray I try to do covers, valley pan, oil pan etc all at once. If your engine is together you could degrease any assembly lube from all surfaces with something like Prepsol and just spray everything at once. Alternatively you might want to remove the intake manifold and valve covers and mask as required so you can get paint down into the valley cover. I beleive the factory just shot everything at once but they weren't too concerned with overspray or poor coverage. All they were worried about was getting it out the door........Bob

Link to comment
Share on other sites

Yeah I hear you about the factory lack of concern. It was apparent in the lack of coverage on many parts of the block.

That being said I do have the engine assembled as I wanted to duplicate the factory finish as much as possible. I did leave the intake and spark plug covers off so I could get maximum coverage of the valley cover, engine block and valve covers. :D

I'll just hang them and spray at the same time.

I think at this point I will thin as you described and spray away.

Thanks again for all the responses.

Rich

Link to comment
Share on other sites

  • 2 weeks later...
Guest pete324rock

Been there ,done that...but I didn't use the gun you mention..it was an electric sprayer....but it worked fine.Bills paint is real good stuff....and hate to disagree,but please don't waste a good job by using a brush or similar. Also,If you haven't already,use stones to grind all flashing off the block if you want a better job.They remove metal fast and is way better than what is there previous..for sure.

Lacquer thinner is the way to go for thinning and since the paint bill sells sets up so fast,you can either thin a lot or a little,according to what your gun setup will spray without spitting,since the paint is so heavy.Other than that...you will be very pleased with the results. What color are you spraying? I did some metallic blue and it was not as good but with a brush was horrible,so spraying was the answer. I also did some exhaust manifolds. Ground them all down...boy were they sad looking before. Used the grey exhaust paint-hi heat...started using a foam brush and it dried so quick,it did a horrible job so I ended that and got the sprayer out and holy cow,what a beautiful job-showroom manifolds. Hope that helps........and that is damm good paint! oh and plus you will lacquer thinner anyways since that is the only thing that will clean that paint up...nothing else will touch it.

Link to comment
Share on other sites

Hobby shops and craft supply store sell a small air brush with a very small jar to hold the paint. I think it was under $10.00.

This is what I used to sparay my engine and small parts. It is great because the cleanup is easy. The only headache is that the jar is small and you have to refill it often.

The spray volume is adjusted by screwing in or out the tip.

I bought a quart of acrylic enamel reducer from the local auto paint store. It was around $20.00 if I remember correctly. The stuf that they sell at the local home imporvement store is not good. I asked for warm weather reducer.

I only thinned a small portion of paint, what I estimated I needed for the job, rather than thinning the whole can.

I thinned it by watching how fast the paint ran off the screwdriver blade and adjusted the consistancy after sparying a piece of cardboard. Not very exact but with such a small amount of paint, a viscosimeter was too big.

Fred Rawling

Bellflower, Ca

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...