Jump to content
JohnnyO

Series 1 Engine Paint Plan - Details Please

Recommended Posts

Does the alternator you pictured have a part number engraved into the housing? There were actually two grapefruit alternators, one for the L20 and one for the L24 with different part numbers. I think that #210 could be a gold mine of originality info. Standby for being pestered by me.

In your picture, you show that little oil press. sending unit wiring minder which is bolted to front engine mount. Would you, or anyone, happen to have an extra one of these little minder hooks available for sale?

Dan, it does have something engraved on the top. I tried to clean it off quickly, but I probably need to take it off to see it better. If you look at the first picture Kats attached in the post in the other thread, it looks like there is a Hitachi symbol and some writting, maybe a part number. Kats says the Hitachi part is #LT145-35. The parts catalog shows the Nissan part #23100-A4800 for the early 40A alternator.

As for the oil pressure sending unit wiring minder, I checked my low mileage 72 and it also has it, so apparently it is not just an early item. It is missing from #32, however. Unfortunately, I don't think I have any spares.

Keep the questions coming. I think #210 will be a good reference car, I just wish it was warmer and I had more time to spend with it.

-Mike

Share this post


Link to post
Share on other sites

Kats says the Hitachi part is #LT145-35. The parts catalog shows the Nissan part #23100-A4800 for the early 40A alternator.

Keep the questions coming. I think #210 will be a good reference car, I just wish it was warmer and I had more time to spend with it.

-Mike

Thanks, Mike. That is my point of confusion. I have two alternators with the following engraved in the housing.

# 1. LT140-53 104 (Not LT145-35 as Kats references)

23100 A4800

# 2. LT145-35B105

23100-E5200

But my FSM engine book on page EE-20 says the Hitachi LT145-35 is for an

L24 engine with an output of 12V-45A, and the Hitchi LT 140-53 is for an L20A engine with an output of 12V-40A.

Both of these grapefruit alternators appear to be identical in appearance, otherwise. Our parts CD shows the original alternator is 23100 A4800 with an output of 12V-40A.

When the weather warms and you get into cleaning under the hood, you may hold the definitive answer as to what is correct.

Thanks, Mike.

Dan

Edited by AZ-240z

Share this post


Link to post
Share on other sites

I concur, Dan. My Nov. 1969 engine manual lists the same information however the parts catalog says 40amp. I don't know why. I'll have to dig mine out and have a look at the stampings on the castings. In the mean time, a couple of pictures to reference the color blue and the overspray on the oil pan. The oil pan in front is correct for early engines as it has the reinforced plate on the side. Service bulletin TS70-28 from August 21, 1970 shows an eight counterweight crankshaft replacing the six counterweight shaft. As I have understood, this was due to vibrations which I believe caused the oil pan to crack. Thus engine serial #'s prior to L24-3607 would have the reinforced pan. Notice the paint "overspray".

post-4148-14150805745535_thumb.jpg

post-4148-14150805745881_thumb.jpg

Share this post


Link to post
Share on other sites
The oil pan in front is correct for early engines as it has the reinforced plate on the side. Service bulletin TS70-28 from August 21, 1970 shows an eight counterweight crankshaft replacing the six counterweight shaft. As I have understood, this was due to vibrations which I believe caused the oil pan to crack. Thus engine serial #'s prior to L24-3607 would have the reinforced pan. Notice the paint "overspray".

That answers my next question "how do you tell the difference."

I guess the easiest way is the ribs. The PO painted the whole oil pan blue. Guess he took over spray to the extreme.

Thanks

Share this post


Link to post
Share on other sites

The oil pan from 26th restored. The plate on the side was actually braised to the pan. Now a question I have. Was the alternator pulley painted or plated? I know the fan blades are plated, but the engine service manual, even though black and white photographs, shows what appears to be a painted pulley.

post-4148-14150805746158_thumb.jpg

post-4148-1415080574666_thumb.jpg

Share this post


Link to post
Share on other sites

Here is the alternator on #32 (its a little cleaner) ;). I tried lighting it and taking pictures from several different angles and these where the best I could do. I think it has something that ends in 45 on the top and maybe 904 below that? I don't know, I look at this stuff too long and its like looking at inkblots, I could pretty much turn it into anything.

-Mike

post-9102-14150805748653_thumb.jpg

post-9102-14150805749246_thumb.jpg

post-9102-14150805749713_thumb.jpg

Share this post


Link to post
Share on other sites

Back to the paint plan for a minute.

Is it common for the aluminum valve cover to "oxidize" black over time?

Should I leave it that way or buff it out?

At first I thought the po had painted it but aircraft remover did nothing so I hit it with a buffing wheel and some polishing compound and it came clean immediately.

What is correct?

John

Share this post


Link to post
Share on other sites

You could always glass bead blast it and it would come out looking very close to stock from the factory. I think a buffing will wheel with compound will give it too polished a look for stock.

I have a thing for shiny things though and am currently polishing mine but it is quite pitted and taking awhile with the 400/600 grits before going to 1000 and buffing.

Share this post


Link to post
Share on other sites
Here is the alternator on #32 (its a little cleaner) ;). I tried lighting it and taking pictures from several different angles and these where the best I could do. I think it has something that ends in 45 on the top and maybe 904 below that? I don't know, I look at this stuff too long and its like looking at inkblots, I could pretty much turn it into anything.

-Mike

Thanks, Mike. I won't be home for a few days, but when I return I will try to upload a couple of pics of my alternators with the inscriptions for comparison.

The engraved parts numbers may be on a part of the housing closer to the mounting pin.

Dan

Share this post


Link to post
Share on other sites

Back to the paint plan for a minute.

Is it common for the aluminum valve cover to "oxidize" black over time?

No - aluminum will oxidize to a white power.

Should I leave it that way or buff it out?

Leave it what way???

At first I thought the po had painted it but aircraft remover did nothing so I hit it with a buffing wheel and some polishing compound and it came clean immediately.

Clean Aluminum or clean black????

What is correct?

Clean cast aluminum is stock.

Has the valve cover been Black Anodized? Did buffing it result in semi-gloss black??

FWIW,

Carl B.

Share this post


Link to post
Share on other sites

Is it common for the aluminum valve cover to "oxidize" black over time?

Maybe the PO have tried to clean the cover with the wrong acid, some acid will make aluminum look black, you can try to clean it with the right acid, have a look at Caswell plating's homepage.

Chris

Share this post


Link to post
Share on other sites
Clean Aluminum or clean black????

I buffed an area the size of a nickel and it came out as clean aluminum. That is why I thought maybe it was oxidized or maybe I should have said tarnished.

Clean Aluminum or clean black????

Clean cast aluminum is stock.

Has the valve cover been Black Anodized? Did buffing it result in semi-gloss black??

I dont think it was anodized. I first thought it was painted because the black (dark grey actually) was uniform, not pitted or raised.

Carl, what do you use to clean these up? I dont want the polished look. I got over shiny objects at about 3 years old:)

TIA,

John

Share this post


Link to post
Share on other sites

Hi John:

I glass bead blast them... with a medium/fine bead. They usually come out of the blast cabinet looking pretty close to new. Mild bead blasting will usually remove most surface stains - - but you don't want to get carried away with the pressure. You also don't want to leave any media inside under the baffels etc.

Finish off with a very light coat of "Dull Amuminum" paint - to retard oxidation and help prevent stains.

FWIW,

Carl B.

Share this post


Link to post
Share on other sites
Now a question I have. Was the alternator pulley painted or plated? I know the fan blades are plated, but the engine service manual, even though black and white photographs, shows what appears to be a painted pulley.

Chris, that has been a quandry for me, also. I have always thought that the pulley was painted a semigloss black with the fan done in yellow cad or zinc.

I bought a factory remanuf. grapefruit alternator on ebay, factory stickers and all, that had that finish. I also have a second reconditioned grapefruit alternator I purchased locally from an auto electric shop. It, too, had a black painted pulley and am assuming the shop just redid the original finishes.

I, also, have a picture of a white '72 z with 16M original miles on it showing a yellow plated fan and pulley. I am leaning toward the black pulley finish right now.

Dan

Share this post


Link to post
Share on other sites

Hi John:

I glass bead blast them... with a medium/fine bead. They usually come out of the blast cabinet looking pretty close to new. Mild bead blasting will usually remove most surface stains - - but you don't want to get carried away with the pressure. You also don't want to leave any media inside under the baffels etc.

Finish off with a very light coat of "Dull Amuminum" paint - to retard oxidation and help prevent stains.

FWIW,

Carl B.

Thanks Carl. I am going to get started right now. I just came back with the needed supplies.

I will post pictures here.

Thanks All!

Share this post


Link to post
Share on other sites
Post before and after pics when you do it would love to see the progress :)

Here are the pictures. I think it turned out nice. I blasted the thermostat cover also to get a feel for the correct pressure. I ended up blasting all the old finish off at about 70 psi with 80 grit glass beads. This did a pretty good job but left some "shadowing" in area so after the worst of it was clean I followed it up with a brief 90 psi blast to even it out.

I painted the thermostat housing with aluminum hi-temp paint. I am unsure whether I like the look or not. Maybe clear?

John

post-17819-14150805778106_thumb.jpg

post-17819-14150805778744_thumb.jpg

post-17819-1415080577934_thumb.jpg

post-17819-14150805780055_thumb.jpg

Share this post


Link to post
Share on other sites

Johnny'O - Nice work.

Carl recommended a "dull aluminum" paint. I've experimented with that stuff recently, and can say IMO it gives a better final look than a clear coat. Clear coat is nice, but it darkens the media blasted surface (kind of looks 'wet', a shade or two darker).

For looks, my first preference on these aluminum parts is just media blasted with no finish coat. But, the parts are prone to staining/discoloring when they encounter various fluids, and as Carl mentioned, oxidation. Second is hi-temp dull aluminum. Honestly, it makes them look great, and gives them a protective coating. Third, and still acceptable IMO, is a hi-temp clear coat.

From what I see in your picture, you likely used a glossy aluminum. For my taste, and I think yours based on your comment, it's just too shiny. Give the dull stuff a try and I think you'll be quite pleased. I am using a product off the shelf at NAPA - "VHT" (Very High Temperature) Header Paint - Flat Aluminum/Aluminum Matte - Product # SP-117. Give it a try. I'm confident you will be pleased.

Attached are several pictures of two parts; both glass beaded, one clear coated, the other (on the right) painted with the VHT.

post-9676-14150805807_thumb.jpg

post-9676-14150805807307_thumb.jpg

post-9676-14150805807495_thumb.jpg

There are lots of other 'before & after' pictures in my gallery as well. I'm having a real blast with my blaster.... addicting, aren't they??

Share this post


Link to post
Share on other sites

John,

I agree. The clear gives it a wet look at least 1 shade darker but I did prefer that look over the standard Plasti-Kote Aluminum paint I found locally.

I use VHT clear satin from napa, I will run by there today and pick up VHT Flat Aluminum and see how it looks.

Thanks,

John

Share this post


Link to post
Share on other sites

I refinished most of the parts for the motor last summer, and I had the flat aluminum and the shiny aluminum paint. I didnt like the look of the shiny aluminum, and the dull was just a tad too dull. So I painted everything with the shiny one, then misted on the dull one to tone it down. Engine is all wrapped up in the garage but I'll see if I have any pics...

Share this post


Link to post
Share on other sites
I refinished most of the parts for the motor last summer' date=' and I had the flat aluminum and the shiny aluminum paint. I didnt like the look of the shiny aluminum, and the dull was just a tad too dull. So I painted everything with the shiny one, then misted on the dull one to tone it down. Engine is all wrapped up in the garage but I'll see if I have any pics...[/quote']

Interesting approach, Zak's Z. I'd be interested in pictures! Thanks!

Share this post


Link to post
Share on other sites

I went with the flat aluminum as Carl and DeesZ suggested. The finish on the thermostat housing was almost an exact match to the unfinished cam cover.

I think I will leave at that for now although I may try Zaks approach with some other small pieces as I move forward.

Thanks all!

John

Share this post


Link to post
Share on other sites

I bead blasted all the parts in the 510 and then painted with a light coat of aluminum wheel paint followed with poly satin clear by minwax. I have been told that stuff holds up best on aluminim in an engine bay. here are the pix. before and after

post-16082-14150805811418_thumb.jpg

post-16082-1415080581205_thumb.jpg

post-16082-14150805812562_thumb.jpg

Share this post


Link to post
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...

Important Information

By using this site, you agree to our Terms of Use. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.