Flat top carbs and I need help

[alordzot]

I am trying to get a 73z started after 13 years of sitting and I have a few questions.

1. What oil do you put into the carbs the book calls for something called everyman oil. what the heck it that and what is the current replacement for it.

2. How much should I put in. There does not seem to be a measure stick or line on it. Please note that they are not dry just low on the oil.

3. I put a few gallons of new gas into the tank and sloshed it around then drained it out. Varnish city. I also pumped new fule through the fule lines to clean them out.

4. Any help in general with getting the car started would be of great help.

Lordzot

[MikeW]

The oil in the carbs is probably the least of your problems (since we're talking about flat tops) but Nissan recommended 20 weight oil. Some people use ATF and others use something else. It's not really critical as the oil is just used to dampen the movement of the piston up and down. A lighter oil allows the piston to move faster which increases throttle response.

[alordzot]

Thank you for your info... Using a small amount of starter juce the engine starts and runs for a short period. . gass is flowing through the mech pump and there is spark... I think the issue is in the flathead SU's... Is that gie in Wash state or the west coast still rebuilding them and or replacing them when you send them the core? does any one know?

[MikeW]

Originally posted by alordzot

Is that gie in Wash state or the west coast still rebuilding them and or replacing them when you send them the core? does any one know?

I'm guessing you're thinking about ZTherapy (which used to be in Idaho but was sold to someone in Oregon)

This particular page should be of interest to you:

http://www.ztherapy.com/technical_stuff/spotterguides/zcar/240spotter.htm

[alordzot]

That what I was looking for thanks alot.. Has any of the Club done this and Can anyone give me an idea if it is worth the time and cash to do it?

[MikeW]

Well. it's not going to take a lot of your time, just your money. It looks like ZTherapy will charge you $950 for a pair of rebuilt round tops. MSA charges $600 plus a $300 core charge for the same.

Your other option would be to find a used pair and rebuild them yourself (trading time for money). Perhaps someone around here has some.

[Zedrally]

If you want to go the send out way, then you may as well get a set of round tops.

On the other hand a re-build kit is available for flat tops, it's cost is considerably less than $900US and regardless of what others say, flat tops if they have been re-built as per manufactures instructions [ie follow the book correctly], will perform better than round tops!

At the end of the day the choice is yours.

Good luck.

[1wildzer]

Why do people say that round top SU's are better than Flat top.

[Zedrally]

Because they don't understand them!

[Zedrally]

Oh boy, I'll start ducking for cover now!!!!

Rather than you ask I'll jump in first.

Firstly the greatest difference is that the mixture cannot be adjusted during tune-up.

There is one other difference that being an addition of a vaccum type acelerator pump, once again when properly O/Hauled presents no difficulty.

Flat tops are factory preset on the lean side, they can however be adjusted during a re-build, simply by altering the float level.

I've been running both types of carbs in different conditions.

On the street and cruising the flats are great, economical and responsive. Note though they have been re-built.

Do not expect as new response from a 30 year old carbie that hasn't been re-built. [which is one reason I think everyone cans them]?

The Kits are available and if you follow the instructions then I see no reason why you can't have a go at it yourself.

As I wrote earlier, if you're looking at sending them out then you may as well change over to rounds, ifyou don't understand carbie's then take the easy way out at this stage, swap over, keep those flats and one day buy the kit and have a go at a re-build.

[240 in OZ]

Mike W

Sorry to disagree on your comments re oil type not important for the carbs. Too thick and it will be sucked into the engine and too light and it is useless.

I have found a mix of sewing machine oil and general engine oil works best.

Joseph

[MikeW]

Originally posted by 240 in OZ

Sorry to disagree on your comments re oil type not important for the carbs. Too thick and it will be sucked into the engine and too light and it is useless.

I didn't say it wasn't important. I said it wasn't critical. The fact that many people use different things (and mixtures of things) means that what you use doesn't have to be exactly what Nissan says to use. The original poster was trying to figure out what oil to use as it related to a car that hadn't run in 13 years. I'd try to get it running before tweaking the oil.