Author Topic: CVZ-18 restore thread...part 2 (Read 164914 times)

dorelse · « **Reply #60 on:** December 11, 2010, 02:58:17 PM »

Yeah, there's extra screens internally to keep the sparks from igniting any fuel vapor.

I actually have a good Mercury Thunderbolt IV distributor already.

floater1 · « **Reply #61 on:** December 11, 2010, 04:41:32 PM »

Quote from: dorelse on December 11, 2010, 02:58:17 PM

Yeah, there's extra screens internally to keep the sparks from igniting any fuel vapor.

So thats all they do to make it "marine" so they can charge you almost twice as much as an automotive unit?

Rich_V174SS · « **Reply #62 on:** December 11, 2010, 04:47:37 PM »

The marine alternators that I've seen also use either mechanical (centrifugal) or electronic advance, not vacuum advance like the automotive distributors of the day. The Thunderbolt IV and V systems from Mercury are electronically controlled and use an optical or magnetic timing sensor under the cap, no points or condenser.

dorelse · « **Reply #63 on:** December 11, 2010, 05:51:32 PM »

Quote from: floater1 on December 11, 2010, 04:41:32 PM

Quote from: dorelse on December 11, 2010, 02:58:17 PM
Yeah, there's extra screens internally to keep the sparks from igniting any fuel vapor.

So thats all they do to make it "marine" so they can charge you almost twice as much as an automotive unit?

Yeah...what Rich said...plus...for $300, if it keeps the family safe...there's really no price on that.

dorelse · « **Reply #64 on:** December 14, 2010, 03:37:41 PM »

So...gonna express some frustration. I need a second valve cover breather valve on my engine. Go to the local dealer today only to have them print off a list of dealers who "might" have them in stock...as they're no longer available, and I'll be "lucky if I can find one".

(Which is fine...I usually try to patronage the local guys...as they've been pretty good to me so far.)

But com'on...ebay, iboats, etc, store after store has them...and most are new, and not even used. I swear these guys don't want me to give them $.

It really has depended on which guy is at the parts counter...so...I'll do it myself.

dorelse · « **Reply #65 on:** December 28, 2010, 07:57:42 PM »

Hey...what is this part & what does it do? Teaching yourself this stuff is hard...so its probably a really dumb question:

Rich_V174SS · « **Reply #66 on:** December 28, 2010, 08:19:42 PM »

Oh I know, I know!!!!

If you didn't have the electric choke pull-off coil on the carburetor directly above then there would be a thermostatic pull-off coil mounted in that location with linkage connecting it to the choke lever on the carburetor - or - in the case of really old engines (maybe 60's-70's) there might be a heat transfer tube wrapped with insulation connecting that plate to the choke coil on the carburetor. But since your choke pull-off is electric neither are required. Now I'm anticipating your next question - where is the wire that connected to the terminal on your electric choke coil? It should be purple with a white stripe?

It would be part of the original engine wiring harness along with the Thunderbolt ignition distributor system. If not then you'll probably have to tap off from a 12v ignition source that's live when the key is in the on position.

dorelse · « **Reply #67 on:** December 28, 2010, 09:15:07 PM »

Actually...my next question was gonna be...do I need to do something with it? (ie...cover it up? replace it with a flat cover or something? It looks open to the intake?)

I actually have 2 complete wiring harnesses for the engine, and I'm hoping I can trust the Clymer's wiring schematic to finish up the wiring.

Thanks Rich!

Rich_V174SS · « **Reply #68 on:** December 28, 2010, 09:22:02 PM »

That plate is not open to the intake (at least it shouldn't be). I think that plate is the cover with a gasket, and the holes are the ends of a small metal tube that's coiled underneath sitting within the flow of engine coolant to pickup and transfer heat for the choke.

OleRed · « **Reply #69 on:** December 28, 2010, 10:37:01 PM »

Rich is right, it is a heat tube, but it is heated by exhaust gases, that port is a cross-over of exhaust from one head to the other, there is a gasket under the plate, it it don't leak any exhaust, I wouldn't try to remove those little bolts, they are notorious for twisting off rather than twisting out. There are little "block" plates that come with an intake manifold gasket set that you can place there to block off those ports when installing the intake manifold.

Jerry · « **Reply #70 on:** December 29, 2010, 07:58:50 AM »

Choke stove.

OleRed · « **Reply #71 on:** December 29, 2010, 09:34:18 AM »

LOL .. never heard it called that, but that is what it is. Hey Jerry, when an electric choke assy is installed on the carb, rather than the vacumn kind, don't the electric choke assy close off the vacumn port that draws the heat through the bi-metal spring ?

Rich_V174SS · « **Reply #72 on:** December 29, 2010, 05:04:05 PM »

I think so.

Jerry · « **Reply #73 on:** December 30, 2010, 02:37:16 AM »

A carb that uses an electric choke doesn't have a vacuum tube. If it does it's used too.

Rich_V174SS · « **Reply #74 on:** December 30, 2010, 06:57:18 AM »

I've rebuild a ton of those carbs. I think the vacuum channel is still part of the carb but the orifice is blocked off when using the electric choke by the choke housing so there's no vacuum leak. The non-electric choke housings have a kick-open piston that uses the vacuum to open the choke slightly for warm-up as well as draw in the heat from the tube that goes into the manifold, the electric choke housings do not so they don't have that vacuum port drilled opened, they are closed when the housing is molded.

Rich_V174SS · « **Reply #75 on:** December 30, 2010, 07:06:58 PM »

Lemme rephrase my last entry - Some of the electric choke housings still use the vacuum port to kick open the choke once the engine is started, some do not. On those two-barrel carbs they do. On carbs like my four-barrel Rochester Q-jet it has a separate vacuum pull-off with linkage to hold open the choke once the engine is running.

dorelse · « **Reply #76 on:** February 05, 2011, 08:31:34 PM »

Am I the only one going stir crazy? It was 35 here today, so I fired up the little space heater and made some more progress.

New Oil Pressure sender installed. (Original one didn't clear the distributor.)

Attached an exhaust manifold & hoses:

and...broke my new starter...

OleRed · « **Reply #77 on:** February 05, 2011, 11:06:37 PM »

Wow ! that too bad Doran, but it's not that big a deal to have a new nose put on the starter, any starter shop can do that. One thing though, it's less apt to break the holes out if you use the right bolts, the original starter bolts have a "nurled" shoulder, and a washer type head, so you don't need a washer, and remember to sgug em up together them tighten em up the same way, just be sure not to tighten one bolt up all the way when the other is not snugged up pretty good. No Sweat .. just take a breath, grin about it and git-er-done

dorelse · « **Reply #78 on:** February 05, 2011, 11:34:30 PM »

Yeah, I had to use new bolts...this starter is much smaller than my old giant of a starter...so the original bolts are about 1/2" too long...couldn't use them. The issue is that the mounting brackets are all hollowed out and don't line up correctly with where the motor meets the old one. It broke before even torquing it. I had just tightened them up with my little socket set. The piece that broke doesn't even hit the block.

I need to get the old one rebuilt and just stick with that. If this is the worst that happens I'll be just fine. I'm putting this together having never seen it assembled, and never having done anything more than change the oil in my cars, and a thermostat once...so...the learning process continues.

You are right though, that additional shoulder probably would have applied more even pressure, I get that now after thinking through your comments. Good stuff!

Thanks Red.

Rosscoe · « **Reply #79 on:** February 07, 2011, 08:28:54 PM »

Motors looking good Doran. Is there room behind the motor to hook up the exhaust down below or did you do that first?