620 Carburetor issue

[Hallow]

Hi all,

 

I am trying to finally get my '79 620 running. I decided to rebuild the carburetor (it wasn't running well when I parked it), got frustrated with the rebuild and ordered a reman from National carbs. I went to install it yesterday and noticed there are some differences with it from the stock.

 

https://goo.gl/photos/2XVpXZrrhmYvvY8m6

 

https://goo.gl/photos/dW1KwEBuhctkfqnA6

 

The old carb has a plate covering where the new one has a vacuum control solonoid

 

https://goo.gl/photos/4DG5qq4eorxojDeF9

 

parts number 24 and 27 on that diagram. I have no recollection of ever pulling them off, but that doesn't mean I didn't

 

Further, while I can see where the electric choke (blue wire)and other solonoid (red wire) hook to in the truck, this vacuum control solenoid has a white wire. The only white wire I see is this piece:

 

https://goo.gl/photos/YG2cWJcpQjx2PGV48

 

That is looking at the intake, the orange rag is covering it up. I have no idea what form of devilry that part is. And it's been so long since I took all this off, I don't exactly remember where it connects.

 

Does anyone have any idea what's going on? Can I simply remove the vacuum control solenoid and put the cover on the reman? If I goof'd and the cover isn't supposed to be there on the old carb, where does it go?

 

Any help and advise would be much appreciated. I really miss driving this thing.

 

-Harris

 

 

[Hallow]

As I look further into this, I am beginning to think the motor has been swapped and is not an L20-B. Can anyone let me know where I can look on the block to confirm this?

[hobospyder]

try using photobucket or something for image hosting. there's a thread in general discussion on how to do it. not everyone is willing to click links.

 

if you look at the passenger side of the engine block just below the head there's a flat spot where the engine "model"/size will be inscribed. kinda above #4 spark plug

[datzenmike]

I refuse to open a link.

 

 

The engine ID is directly behind the dip stick handle on the block where it meets the aluminum head. Should say L20B if a '75-'79 620.

 

The '78 and '79 620 used a W58 head. Look along the lower edge just behind the fuel pump and between the #1 and #2 spark plugs. Says MADE IN JAPAN  W58.

 

The '75-through '77 used a U67 head.

 

Very possible the carb was swapped.

 

The '73 through '77 did have a BCDD vacum cut solenoid.

The '78 and '79 did not have a BCDD vacuum cut solenoid .

[Hallow]

Thank you both!

 

I had to scrape away old dried oil, but I found "L18" and "Made in Japan A87". 

 

Theory confirmed. Engine was swapped. I imagine then this means I need the carburetor out of a 610 or 710? 

[hobospyder]

no, 74 620 came with the l18. don't see why an l20b or even l16 carb wouldn't work. most people swap for a weber 32/36 dgv(manual choke) or dgev(electric choke).

[Hallow]

I got the 510 or 710 from National Carburetors website. They have the L18 listed under 510 and 710. Thanks for the correction.

 

I had originally purchased a weber after reading quite a few threads on this forum about them. When it arrived there was a note in it saying "Not CA Legal". So back it went. 

 

If I were to install the carb I have that is meant for an L20b, how or where would I hook up the solenoids the original didn't seem to have?

 

Thank you again for your quick and clear responses. 

[datzenmike]

By California law isn't it illegal to put an older year engine into your vehicle if it's newer than a '74 anyway? In theory it won't pass a visual inspection let alone an emissions test.

 

 

That wire should go to the BCDD relay which is activated by a switch in the speedometer for speed above 10 MPH. Your '79 won't have any of this and why older engines are not allowed.

 

 Not judging you here, not saying you are wrong or criminal or illegal... don't even care. Just be aware that you may have trouble getting this to pass any inspection.

[Hallow]

I appreciate the concern and heads up, and as far as I know, you are correct. However, this thing has passed smog before, so I don't think the techs look too closely at the particular make and model and cross reference it with which year and model has what engine. 

 

Should I bother trying to fiddle with this carburetor or should I try to send it back and get one meant for an L-18?

[datzenmike]

Well if it passes emissions and you are replacing it, get the carb for the '74 620 L18.