Author Topic: Yet another Engine Painting thread  (Read 4754 times)

0 Members and 1 Guest are viewing this topic.

Offline grepper

  • Busted Knuckles
  • Enthusiast
  • **
  • Posts: 166
Yet another Engine Painting thread
« on: October 18, 2013, 08:27:56 AM »
Some say it’s pretty cheesy to paint an engine whole.  Well…  It still has good compression, so why take it apart?  It just looked like crap.

I have had limited luck painting engines.  Like everyone says, it’s all about the prep work.  So here I go again. 
First I did several passes with degreaser, scrubbing with a long bristle brush, and shooting it with a power washer.   Then I did a couple of passes with paint remover and power washing.  Scrubbed it again with a long bristle wire brush.  Did a bit of sanding to clean up some aluminum oxidization spots, the real visible areas and where I could reach.   Blew it off with compressed air.  Then wiped it down with acetone.   Oh yeah, for all the aluminum covers that will get polished, I took them off and cleaned up the gasket surfaces, then put them back on.    The point here is so that I don’t end up scratching my new paint trying to remove old gaskets.   After the acetone, I only touched the engine with rubber gloves on.   I masked it off, shot it with VHT Engine Enamel , and let it dry for a day.   I read a few reviews on different engine paints.   Duplicolor got OK reviews, VHT and POR15 got better.  VHT was available at the local auto parts store, plus lots of people on this forum said it matched the original Honda case color.
 




Now for the tricky part, how to cure it properly (200 degrees for 1 hour).   Sure if I had the engine apart, I could cure it in the kitchen oven (while the wife was out… ha ha), but a big inline 4 is not going to fit.  So I made my own curing box.   I kept the big box from the BBQ we bought this summer, lined it with aluminum foil so it would reflect the heat.  Yeah I used Duct Tape, not real heat tape, hoping it could stay together at 200 degrees.   



Cut a hole in one bottom corner for my Heat gun, poked a cooking thermometer in the opposite top corner. 





As you can see, I’m starting out at 63 degrees.    There’s also a hole on top so I can regulate the heat by covering it, and so I can see inside.  Making sure the heat gun isn’t pointing right at any part of the engine, and I’m not touching the inside of the box.  Turned the heat gun on low and watched the temperature climb. 



After about a half hour or so it seemed to top out at 130 degrees.  So I kicked it up to high and laid some towels around the bottom edges.   The temperature steadily climbed up to 195, now we are cooking!  Since my first half hour was only at 130, I let it cook for another 45 minutes or so. 



At some points it got up to 205 and I would open the hole a little.   After cooling off an hour or so, the engine was still pretty warm.  I did a fingernail test and that paint is as hard as a rock now.. 

I did baby sit the process closely.  Cardboard combusts at 450 degrees :D

Now for the top half







BTW:  Yes I know I painted the front sprocket, it's getting replaced anyways.

Looking great!


Offline Tews19

  • I am no
  • Really Old Timer ...
  • *******
  • Posts: 6,465
Re: Yet another Engine Painting thread
« Reply #1 on: October 18, 2013, 08:38:57 AM »
Very ingenious.
1969 Honda CB750... Basket case
1970 Honda CB750 survivor.

Offline iron_worker

  • Master
  • *****
  • Posts: 2,081
Re: Yet another Engine Painting thread
« Reply #2 on: October 18, 2013, 09:32:00 AM »
Clever. Very clever.

Hopefully it holds up for you for a long time.

IW

Offline SF

  • Hot Shot
  • ***
  • Posts: 527
  • I burn gas very well
Re: Yet another Engine Painting thread
« Reply #3 on: October 18, 2013, 09:39:16 AM »
looks beautiful, nice job on the covers to
92 wr250 sold
98 zx6r sold
04 zx10r
73 cb350 twin
75 cb550f
75 cb550f
72 r5c
rgid springer bobber project

Offline rb550four

  • Master
  • *****
  • Posts: 2,472
  • I'm nobody's slave and nobody's master
Re: Yet another Engine Painting thread
« Reply #4 on: October 18, 2013, 08:13:38 PM »
The paint looks great!
But I am wondering if  you drained the oil and  took the oil pan off to insure that there was no crud laying in it before you flipped that motor over.
That paint looks great!
A few Honda 500's, a few Honda 550's, a few Honda 650's, '72 cb 450, a couple 500/550/650 hybrids, and 2001 750. 
  550 Snowbike -Somebody had to do it.
  http://forums.sohc4.net/index.php/topic,101678.0.html             
http://forums.sohc4.net/index.php/topic,137317.msg1550907.html#msg1550907

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 19,905
  • Saver of unloved motorcycles.
Re: Yet another Engine Painting thread
« Reply #5 on: October 18, 2013, 09:03:12 PM »
Thanks, that's great. I didn't bake mine, than a carb leaked all over it. Washed the uncured paint right off.
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline grepper

  • Busted Knuckles
  • Enthusiast
  • **
  • Posts: 166
Re: Yet another Engine Painting thread
« Reply #6 on: October 20, 2013, 07:13:14 AM »
rb550four:  yes I drained the oil and cleaned the oil pan.  Now that you said that, its good that I did.

Don R:  Same exact thing happened to me on one engine.  It was a Yamaha xs650.  Let it cure by running the engine.  Most of it did great,  except for the part under the carbs, where the case doesn't get that hot.  Sure enough,  had a little gas leak and that's where the paint came off.

Offline toytuff

  • "watching the pinheads"
  • Old Timer
  • ******
  • Posts: 4,349
Re: Yet another Engine Painting thread
« Reply #7 on: October 20, 2013, 08:31:02 AM »
I just love you guys! Great idea right there.  ;)

Looks fantastic to me.  8)

tt

Offline FunJimmy

  • Who you calling
  • Old Timer
  • ******
  • Posts: 3,802
  • Vancouver
Re: Yet another Engine Painting thread
« Reply #8 on: October 20, 2013, 09:03:43 AM »
Great job and brilliant cure oven!
You never see a motorcycle parked outside of a psychiatrist's office!

CB550 Cafe Interceptor a Gentlemans Roadster
http://forums.sohc4.net/index.php?topic=27159.0

Offline David B

  • Enthusiast
  • **
  • Posts: 184
Re: Yet another Engine Painting thread
« Reply #9 on: November 03, 2013, 07:30:53 PM »
Great idea!
DB

Offline Ecks

  • Full Member
  • *
  • Posts: 25
Re: Yet another Engine Painting thread
« Reply #10 on: December 04, 2013, 03:34:47 AM »
Brilliant idea, great to see that it worked out so well.  Now off to see if a hair dryer can be borrowed for a good cause.

One day I hope to have a workshop like yours too, it looks like a great environment.

Offline Ecks

  • Full Member
  • *
  • Posts: 25
Re: Yet another Engine Painting thread
« Reply #11 on: February 24, 2014, 10:46:38 AM »
I just finished heat curing my engine in a very similar manner to yours, box and all.  Putting a blanket over the box boosted the temp up to  285°F before my courage ran out.  The fingernail test awaits.


Offline grepper

  • Busted Knuckles
  • Enthusiast
  • **
  • Posts: 166
Re: Yet another Engine Painting thread
« Reply #12 on: February 24, 2014, 11:03:12 AM »
Hope it works for you.  For me only time will tell how well it worked.

Sent from my SCH-I535 using Tapatalk


Offline Jerry Rxman Griffin aka MuthaF'er

  • This MuthaF'er is getting to be a
  • Really Old Timer ...
  • *******
  • Posts: 14,912
  • Bought her new 4/75
Re: Yet another Engine Painting thread
« Reply #13 on: February 24, 2014, 11:22:34 AM »
Wonder how this would work for a turkey?
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline madScientist

  • Hot Shot
  • ***
  • Posts: 537
Re: Yet another Engine Painting thread
« Reply #14 on: February 24, 2014, 11:30:14 AM »
That's freaking brilliant! I'm doing this for my next engine paint!
You CAN do great things...with enough beer.


78 cb750f
http://forums.sohc4.net/index.php?topic=113293.0
70 CL350 Street Tracker / Cafe
http://forums.sohc4.net/index.php?topic=125641.0
83 KZ1100ltd
76 GL1000
71 Kaw H2 (to be built)
77 cb750A (sold)
74 cb125s (sold)

Offline D-Ral

  • Enthusiast
  • **
  • Posts: 202
Re: Yet another Engine Painting thread
« Reply #15 on: February 24, 2014, 06:12:52 PM »
So, this may sound stupid, but... When you pop the covers off, is it always necessary to replace the gaskets before reinstalling?

Offline Tsunami

  • There's No Place Like This Place Any Where Near This Place So This Must Be "THE PLACE"!
  • Hot Shot
  • ***
  • Posts: 311
  • Life's to Short, Carry On!
Re: Yet another Engine Painting thread
« Reply #16 on: February 24, 2014, 06:28:39 PM »
The man said he would be sending it out for polishing after the paint job, I will bet he used gaskets on finial assy. Looks great, if it aint broke don't fix it!  Learned that the hard way over the years.  Back when V-8's needed the oil changed every 3-5 K miles and topping off in between as they inevitably leaked and burned oil which then became en crusted with dirt on the out side and gunk on the inside.  Woe be to the guy who washed out the inside with kerosene and steam cleaned a good running motor on the outside only to get rattling chunk of iron with loud lifters and a lot of leaks looking for some grunge to plug them up again.  True I swear it!
[Tsunami Build Link]
CL450 early 70's
New 1973 CB750 Flake Sunrise Orange
CB350 Chopper early 70's
CB350 Cafe' early 70's
Honda Cub 90cc late 60's
Other's