The Adventure Begins- My 620 build thread

[Randalla]

I think you're right Carl about the Weber 32-36 DGV carbs. I may end up there, given the difficulty I'll likely have finding an SU manifold for the 620. Thank you to whoever flipped my earlier image (Guy?).

[AZhitman]

Yep, they wouldn't have had SUs.

Lots of folks have had really good luck with the Chinese knockoff of the original Hitachi 2bbl, which means you can save that manifold.

Bring al that stuff over and I'll media blast it for you!

[Randalla]

Thanks for the advice Greg. I'll check out the knock offs. Appreciate your offer to blast the parts, they definitely need it. I have a sand and soda blaster here and will get around to doing that soon. I'm just taking one step each day so it feels like I'm making progress. Yesterday, I cleaned up the battery, both leads, the hold down and the battery tray, among many other small things. Here are a few before and after shots. Battery seems good after using the repair function on my charger It's holding 12.7 volts.

[Randalla]

Do any of you 4-cylinder Datsun guys know if the intake manifold pictured is the stock one for this pickup? It definitely looks different than the 6- cylinder manifolds I'm acquainted with. The plate on the side with RTV remnants (alternate mount for side draft carb?), and the 4 bolts on the thing on the bottom seem odd to me, though it's clearly a Japanese part.

[Duffman]

Randy, have you removed the valve cover yet to see what it looks like underneath?

[insitu_az]

Just hazarding a guess here.

The thing on the bottom of the manifold is the warming plate which connected the input manifold to the original exhaust manifold to heat the manifold for smog control, and the block off plate with RTV is where the previous owner removed the EGR valve.
- Guy

P.S. Yeah, I rotated that picture.

[Randalla]

Guy, thanks for that explanation and for flipping my photo. I'd really prefer to find a intake manifold allowing me to mount a pair or SU's. Know anyone who may have one for sale by chance? Duffman, I pulled the valve cover this morning and the valve train is complete, intact and the cam lobes look great, with no obvious signs of wear. I also removed the huge rear tube bumper this morning and noted the license plate. Looks like it's been over 20 years since the truck was last licensed in 2001.

[Duffman]

Randy, it looks pretty good under that valve cover!

[Randalla]

Changed dirty oil and filter out today for some Rotella 5W-40. Probably will run it for only a 1,000 miles or so since the truck has been sitting so long, I'm sure it will get contaminated pretty quickly. Also found a nice deal on CL on some 17" x 7" wheels. these were take offs from a 2014 Toyota 4-Runner and came with chrome lug nuts, all for $150 . I'll test fit them tomorrow, but they do have the right bolt pattern. I've got to do some calculations to determine optimal tire size. Looks like I need to replace the wheel studs, as the current ones are 12 x 1.25 and the new lug nuts are 12 x 1.5. Actually it was easier and cheaper to replace the lug nuts than the studs.

[Randalla]

So, what is a Condensator? The 620 had this weird looking device mounted on the firewall, with one hose coming out and running to the vent on the valve cover, and the other hose running to the intake manifold. I was curious and did some research to learn if this device provided any real benefit. Today, we would call this a "catch can" or "oil separator." Normally a PCV valve, or PCV system processes crankcase vapors and contaminants back through the engine, in attempt to incinerate the waste. The problem is, over time, those contaminates end up as sludge in your engine. There are some good YouTube videos showing tests of similar units, measuring contaminants getting trapped. The results left me thinking installing one has significant benefit for the environment, the engine's long-term health, and even performance. The unit shown here was produced in Sacramento, CA during the late 70's and early 80's. It's a pretty neat automotive relic. Today' equivalent product is probably much more effective... though I like this one with a clear capture container to see the junk that didn't get recirculated through the engine.