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PostPosted: Tue Mar 06, 2007 8:21 am 
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3 Deuce Weber

Joined: Tue Mar 06, 2007 8:17 am
Posts: 50
Location: Wading River, NY
Car Model:
New to this Websight.
My son (16) bought a Father/Son project. A not running 1970 Valiant 4 door. That has been sitting for years.
The engine came with an Offenhauser Intake and a Holley 8007 Carb.

Last week I pulled and cleaned the carb. After running a secondary gas can to the Fuel Pump, the engine fired up.

So now I have a running engine that runs like total crap. If I try to bring the idle down to where it should be it shakes like crazy and wants to stall. It also wants to die when I put it in gear even at the higher idle. The points, plugs, Rotor and Cap look OK for now,
I have not checked the Timing or even done a compression test on the cylinders yet but my real question is, Do any of you guys/girls have this setup and what Jets are you running? There are so many mysteries to this car that I'm trying to reduce the amount of variables to get it running well.
It also has a nasty Exhaust leak coming from, i think, the mating point of the Exhaust and intake manifold. I heard there is a gasket and bolt down in that area. I'm a Chevy guy so excuse my Mopar stupidity.

_________________
1970 Valiant.. my sons Daily Driver
1975 CJ5, fiberglass body,350/345Hp chevy
1985 chevy stepside pickup, Original Owner
1989 Volvo 240: Original Owner
OTHER TOYS: http://home.no.net/ebrox/Tony's%20cars.htm


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PostPosted: Tue Mar 06, 2007 8:57 am 
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Board Sponsor & Contributor

Joined: Thu Oct 31, 2002 5:39 pm
Posts: 24449
Location: North America
Car Model:
Welcome on the board! It sounds like the previous owner of your car thought he'd turn his Valiant into a zoom-zoom race car by tossing a 4-barrel on it. Bad move on his part; you can make a slant-6 run well with a 4bbl, but it takes a great deal of twiddling and tuning and futzing around, and on an otherwise-stock engine it's way too much carburetor. You'll be very much happier (and wind up tearing out a lot less of your hair) with a 2bbl rather than a 4bbl. Since you will have to remove the manifolds anyhow to correct the exhaust leak, it's a good time to swap on the factory 2bbl "Super Six" setup. These setups go by on a fairly regular basis both in the "Parts For Sale" section of this site and on eBay.

It will be worth your son's while to buy the three books mentioned in this post. Once he's up to speed on general principles and repair techniques, the father/son project will go a lot smoother and yield more fun.

It is definitely worth getting the good gaskets for the manifolds-to-head and the intake-to-exhaust (heat riser/hotbox) junctions. The parts store items you can buy locally don't seal well, especially at the intake-to-exhaust junction. Because your car is a '70, also check carefully atop the #5 (2nd to rearmost) exhaust manifold runner. Originally, an automatic choke thermostat was bolted there. This, on the '70-'72 manifolds, is a gasketed junction. It is likely the PO hacked or tried to remove the choke in some fashion during his 4bbl "conversion", so check for exhaust leaks here, too.

Additional upgrades? Well, you being a Chevy guy, you'll feel right at home with the see HEI upgrade. Install a NAPA Echlin long-tip rotor # MO-3000 with Standard-Bluestreak CH-410X cap. Use NGK ZFR5N spark plugs, which have an extra-long nose that improves economy and driveability in the '60-'74 slant-6s. Stock number on this plug is 3459 in the US, 5699 in Canada. You will need a smaller 5/8"-hex spark plug socket to install these, rather than the 13/16"-hex item you use to remove the old regular plugs. Gap them to 0.045" and install them without their metal ring washers. You'll want to replace the spark plug tube seals (rubber O-rings at the top of each aluminum spark plug tube) at the same time to eliminate a very common oil leak. B45384 will get you a spark plug tube seal at NAPA (you'll need to order six). Or, you can get a set of six from Fel-Pro under P/N ES12794.

The slant-6 in your '70, unless it has been replaced by an '81 or newer engine, has mechanical tappets that require periodic adjustment.

And, once you get the basics taken care of and the engine's running well, the fuel line mod improves cold and hot starting and running.

_________________
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Too many people who were born on third base actually believe they've hit a triple.

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Last edited by SlantSixDan on Tue Oct 30, 2007 10:58 am, edited 3 times in total.

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PostPosted: Tue Mar 06, 2007 10:02 am 
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3 Deuce Weber

Joined: Tue Mar 06, 2007 8:17 am
Posts: 50
Location: Wading River, NY
Car Model:
Thanks
While we dropped the carb back on, I took the hollow shell of the Bimetal Choke off. There was no gasket under the cover.

So that will be tended to. The main leak must be the Intake to Exhaust gasket because there is soot on the bottom of the Intake manifold.

So the earlier engine is Solid lifter. Wasn't sure. I am a total DIYer so I have an account at NAPA. As well as some House Appliance places. This engine absolutely does not scare me, it's just that I'm unfamiliar with it's personality.
The HEI will fit down there? My guess is that the Cap is bigger thatmust be tight OR does this MO-3000 have an Electric box off of it?

OH another issue. Is the Voltage Regulator internal to the Alternator on these early Mopars? I'm putting out way to high...18V. Before I pop something, I better bring that down to earth.

I'll be spending some time doing SEARCHES. I'm sure these questions have been asked a bunch of times.

_________________
1970 Valiant.. my sons Daily Driver
1975 CJ5, fiberglass body,350/345Hp chevy
1985 chevy stepside pickup, Original Owner
1989 Volvo 240: Original Owner
OTHER TOYS: http://home.no.net/ebrox/Tony's%20cars.htm


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PostPosted: Tue Mar 06, 2007 10:45 am 
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Board Sponsor & Contributor

Joined: Thu Oct 31, 2002 5:39 pm
Posts: 24449
Location: North America
Car Model:
Quote:
Thanks
While we dropped the carb back on, I took the hollow shell of the Bimetal Choke off. There was no gasket under the cover.
There's the top cover, then the bottom cup, then the gasket, then the cast iron manifold. There's not meant to be a gasket between the top cover and the bottom cup.
Quote:
The HEI will fit down there? My guess is that the Cap is bigger thatmust be tight OR does this MO-3000 have an Electric box off of it?
Caught you redhanded makin' assumptions! :lol: Go and actually read the link I provided.
Quote:
Is the Voltage Regulator internal to the Alternator on these early Mopars?
No, it's on the firewall.
Quote:
I'm putting out way to high...18V. Before I pop something, I better bring that down to earth.
Yep!

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

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PostPosted: Tue Mar 06, 2007 11:49 am 
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3 Deuce Weber

Joined: Tue Mar 06, 2007 8:17 am
Posts: 50
Location: Wading River, NY
Car Model:
I understand... there was no gasket between the Cup and manifold.

I didn't look at the Link yet... You got me.

Good, I was hoping I didn't have to get an entire alternator. I'm trying to get this up and running on a 16 year olds shoe-string budget until I am comfortable that ithe Six is all worth keeping. When I feel it is a keeper, Dad will jump in financially.
I know this is taboo but a friend of mine has a full running '68 Cuda with a 318. He is building a Hemi for it . Dana 60 rear and some radical Transmission. He is willing to drop the entire drivetrain off at my doorstep. So if I even have to do the Head on this car, I can put in an entire running drivetrain for the price of a K member adapter kit for the motor mount location.
Don't mean to spit on your slant six world.
When I said this was a father/son project I meant that this car was bought as a learning tool for my son. The paln is to get his hands dirty and understand the workings of a basic engine. It was not to Mint out a 4 door valiant. So even if the Six is deamed NG, I will go through the exercise of taking the Head off to show him how and what Pushrods Valves do for a living.
As I mentioned in the first Post.. this weekend is a Compression test to hopefully answer why it's doing what it's doing. I hope all cylinders are OK.

_________________
1970 Valiant.. my sons Daily Driver
1975 CJ5, fiberglass body,350/345Hp chevy
1985 chevy stepside pickup, Original Owner
1989 Volvo 240: Original Owner
OTHER TOYS: http://home.no.net/ebrox/Tony's%20cars.htm


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PostPosted: Tue Mar 06, 2007 12:31 pm 
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Supercharged
User avatar

Joined: Mon Sep 26, 2005 5:09 pm
Posts: 2946
Location: Gilbert, Arizona
Car Model: 1962 Plymouth Valiant Signet
It's not taboo but it's not the way we in this group have chosen to do things. There is nthing wrong with a small block Mopar powerplant in an a-body. Tens of thousands of them were built that way but there is something unique and special about a slant six and most of us feel that is worth preserving.

_________________
David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.


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PostPosted: Tue Mar 06, 2007 1:11 pm 
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Guru
User avatar

Joined: Mon Oct 14, 2002 4:32 pm
Posts: 4880
Location: Working in Silicon Valley, USA
Car Model:
Quote:
...I will go through the exercise of taking the Head off to show him how and what Pushrods Valves do for a living.
As I mentioned in the first Post.. this weekend is a Compression test to hopefully answer why it's doing what it's doing. I hope all cylinders are OK.
As noted above, first pull the valve cover and check the valve lash ajustment. Rough running can be caused by tight valve lash.
Also, double check the firing order, it should be 1-5-3-6-2-4
DD


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PostPosted: Tue Mar 06, 2007 1:23 pm 
Offline
3 Deuce Weber

Joined: Tue Mar 06, 2007 8:17 am
Posts: 50
Location: Wading River, NY
Car Model:
Will do. thanks

_________________
1970 Valiant.. my sons Daily Driver
1975 CJ5, fiberglass body,350/345Hp chevy
1985 chevy stepside pickup, Original Owner
1989 Volvo 240: Original Owner
OTHER TOYS: http://home.no.net/ebrox/Tony's%20cars.htm


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