U20 Rebuild Planning & Parts

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datscarlin
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U20 Rebuild Planning & Parts

Post by datscarlin »

Greetings all. I'm the guy who had the logo'd roadster floormats made for this 311s group a couple of years ago, and I say that only to let you know that requisitioning custom floor mats is about where my roadster mechanical expertise and abilities ends. I am wanting to prepare for a complete rebuild on an original (never previously rebuilt) U20 which will be done under the direction and expertise of my very seasoned professional mechanic (U20/Datsun-experienced) later this year. (The motor is presently running well in my 69 except for chronic/severe and annoying "run-on"/dieseling after ignition turned off. Also, I want to switch to Solex carbs but feels dumb to put a brand new (NOS) disturbingly expensive Solex kit/carbs on an old U20 motor.)

Wondering if someone(s) could advise me on putting together a comprehensive parts shopping list so I can begin to acquire what will be needed. I'd be happy to pay one of you insightful mechanical geniuses for your time and consultation in that regard. My checkbook is ready to acquire necessary best available parts from Dann or Dean or Ross or Paul, but if preparing the shopping list is left to me I will surely fail and, as the saying goes, failure is not an option. It would also be great to have someone to share the insightful and invaluable comments, "whatever you do, make sure you don't do this...."

Thanks for considering; I have been exceedingly grateful for all the help and advice I've benefited from many of you over the past few years.

Don Carlin
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Re: U20 Rebuild Planning & Parts

Post by mwegener111 »

I would add JT to your Vendor list. Always available and quick to reply, and expertly knowledgeable.

www.datsunrestorationproducts.com
datscarlin
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Re: U20 Rebuild Planning & Parts

Post by datscarlin »

Yes, love JT and all of his products. Wasn't thinking he was a purveyor of U20 rebuild components.
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SLOroadster
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Re: U20 Rebuild Planning & Parts

Post by SLOroadster »

I would suggest having the cylinder head gone through. It might need nothing more than new valve seals, it might need new seats and guides, rockers ect. If you are looking ot put a set of Mikunis on, I'd say you will want a B cam at least. You will need either refurbished rockers, or new ones.

There is a decent chance that the pistons can be resused, with new rings. Deves or Hastings both make good rings that aren't that expensive. Assuming no damage to the bores, a hone job will be required. The timing components may or may not need to be replaced. New chains are worth doing because they are cheap even if everything else looks good. The rod and main bearings, there are several choices, any good quality ones should work. I've run Clevite 77s and NDCs in the past. I'm going to give a set of King Bearings a try (not the coated ones.) Do shim both the tensioners. It wouldn't be a bad idea to get everything balanced.

Will
Sorry, I find modern engine swaps revolting. Keep your G, R, or U series in your Roadster!
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bmccarthy67
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Re: U20 Rebuild Planning & Parts

Post by bmccarthy67 »

This may not make sense to all, but I tend to "share the love" on my purchases. I know many have preferred vendors, but since they all do a service to the community I try to use them all. I just did a second U20 rebuild, Pistons/Connecting Rods from Stan, Bearings, Gaskets and stud kit from Dean, Chains, Sprockets, oil pan baffle from JT, externals and add on items from Scott and Mike, head work by Rebello.

As for the list, you'll want to start with your U20 rebuilder you mentioned as they will decide on a simple hone or bore with new piston size based on condition. Obviously a full U20 gasket kit, new bearings...main and rods (STD or undersize?), jackshaft bearings, new chains, sprockets, guides (again, your rebuilder can/will decide if anything old is still serviceable).

The off the memory problem areas are the press fit for the jackshaft bearings (rear one really important as holes line up to oil top end). Cleaning the block means drilling/driving out the plugs in the main oil gallery and those seem to be a unique size. If they've rebuilt U20's they'll have all the bases covered. All of the vendors have always been great walking me through everything.

Good Luck!
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Gregs672000
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Re: U20 Rebuild Planning & Parts

Post by Gregs672000 »

Dean offers complete kits that from what I've seen will cover everything. As Will said, it will depend on what's needed and that won't be known until the motor is apart and inspected. You may or may not need timing gears, some or all (BTW let me know if you do as I have a complete set I ended up not needing, including an adjustable cam gear and bushing kit). No sense in talking pistons etc yet until we know more about the motor, as well as what you desire from it. These are not complicated engines and a good shop should not have any trouble building it right. The manual will be needed for specs etc. The most likely place for error are the timing chains but if they're not sure we have many pics for reference.
Greg Burrows
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JT68
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Re: U20 Rebuild Planning & Parts

Post by JT68 »

Thank you Mike, Buddy and Don!

Don, Yep we have every part needed for U20 rebuild:

Every cylinder head component
Every lower end component, pumps,bearings etc.
Forged Pistons more sizes and types in stock than any other vendor
(If you have cast pistons, chances are they are cracked-we just threw away 8 more from two other U20's we tore down
for rebuilding-100% cracked in the usual spot)

Chromoly Forged Rods for U20. Rebuilt factory U20 Rods
Every timing component- of course we were the first vendor to develop and mass produce adjustable timing gears!
Every cooling system component
NEW Harmonic Balancers.
ARP studs and fasteners
Gasket set
Cams, Even Cylinder heads - rebuilt or bare.

These are just a few items:

https://www.datsunrestorationproducts.com/shop-13
https://www.datsunrestorationproducts.c ... c-balancer
https://www.datsunrestorationproducts.c ... s-set-of-8
https://www.datsunrestorationproducts.com/shop-11
https://www.datsunrestorationproducts.c ... lutch-10lb

We take orders 24/7 30days a month, No "only open 3 days this month silliness" You can reach us 24/7 by text,phone,email,PM

If you don't see it on the webpage, just ask, we have it :)
Last edited by JT68 on Tue May 04, 2021 4:51 pm, edited 1 time in total.
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Only the very BEST parts for your Datsun- 1000's of items in stock
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Re: U20 Rebuild Planning & Parts

Post by Datsunparts.comInc »

datscarlin wrote: Tue May 04, 2021 11:18 am Greetings all. I'm the guy who had the logo'd roadster floormats made for this 311s group a couple of years ago, and I say that only to let you know that requisitioning custom floor mats is about where my roadster mechanical expertise and abilities ends. I am wanting to prepare for a complete rebuild on an original (never previously rebuilt) U20 which will be done under the direction and expertise of my very seasoned professional mechanic (U20/Datsun-experienced) later this year. (The motor is presently running well in my 69 except for chronic/severe and annoying "run-on"/dieseling after ignition turned off. Also, I want to switch to Solex carbs but feels dumb to put a brand new (NOS) disturbingly expensive Solex kit/carbs on an old U20 motor.)

Wondering if someone(s) could advise me on putting together a comprehensive parts shopping list so I can begin to acquire what will be needed. I'd be happy to pay one of you insightful mechanical geniuses for your time and consultation in that regard. My checkbook is ready to acquire necessary best available parts from Dann or Dean or Ross or Paul, but if preparing the shopping list is left to me I will surely fail and, as the saying goes, failure is not an option. It would also be great to have someone to share the insightful and invaluable comments, "whatever you do, make sure you don't do this...."

Thanks for considering; I have been exceedingly grateful for all the help and advice I've benefited from many of you over the past few years.

Don Carlin
Don We have many U20 engine parts like the newer chain guides, jackshaft thrust plate, U20 oil pump that we've been selling for the past 10 years race harmonic balancers and the most complete gasket kit you can buy.
I sell 2 full engine kits for the U20 each month and have for years. Never any complaints on forums or returns ever.
Well enough Dean, just look at the web-site. Don, it speaks volumes. All in stock.

https://www.datsunparts.com/Engine-2000

https://www.datsunparts.com/Engine-Timi ... nents-2000

https://www.datsunparts.com/Engine-Kits-and-Packages
More parts on display in our showroom than most vendors carry in their entire inventory! 2900 active parts numbers in our catalog. End of year 2020 Inventory piece count- 96,155 parts on hand! Check out "Shop A Movie" at our web-site