1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

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Old Mar 22, 2007 | 11:24 PM
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Vassago79rx's Avatar
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Red face New to RX7 World

I own a 79 rx totally stock with 4spd , Last summer when I bought the car it ran fine , didn't drive it much this past winter. Now when I go to drive it , it is harder to crank the engine seems like it is "dragging" but on road it runs fine . Problem is then when I shut it off it lets a backfire loose that would raise the dead, also ideling at times there is a blue flame from exhaust.. Knows I sound totally newbie ,,but I am ,,lol,,Please help!!
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Old Mar 22, 2007 | 11:33 PM
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From: Land Of Confusion southern MI, USA
might be running rich(blue flame) and as far as the slow cranking, i think thats just cause its cold, unless it does it after the car is warmed, then i would look into the battery/alternator replacement. and the backfire is to be expected\, you dont need to worry about that.

and im glad your happy with your car, and welcome to the club.
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Old Mar 22, 2007 | 11:49 PM
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Originally Posted by Vassago79rx
I own a 79 rx totally stock with 4spd , Last summer when I bought the car it ran fine , didn't drive it much this past winter. Now when I go to drive it , it is harder to crank the engine seems like it is "dragging" but on road it runs fine . Problem is then when I shut it off it lets a backfire loose that would raise the dead, also ideling at times there is a blue flame from exhaust.. Knows I sound totally newbie ,,but I am ,,lol,,Please help!!
Harder to crank as in the engine turning slow when cranking?

The inherent backfire problem on the Sa model is sometimes caused by a bad dashpot on the side of the carb. Some models use a vauum type that has a check valve installed on it. If you took the air cleaner off you would see a vacuum hose running from the air horn(upper portion) of the carb over to the dashpot.

What the dashpot does is slow down the return rate of the linkage to keep it from dumping too much fuel on decel.
On the backfiring. If you get on it hard(meaning 3/4 throttle or more) and shift from 1-2,2-3, and 3rd to 4th, does it backfire inbetween shifts?
If it is only doing it a shutoff it is possible that the throttle plate is staying too far open after shutoff. This could be from the throttle cable sticking, being tight or alot of varnish built up on the throttle plates.
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Old Mar 22, 2007 | 11:53 PM
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Yes harder to crank as in the engine turning slower, And yes it backfires when I get on it hard, the backfire when I shut it down is loud enough to bring people out of my daughters scholl when I pick her up ,,,,,
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Old Mar 23, 2007 | 12:07 AM
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Find the FSM link from member trochoid profile and test the dashpot function first.

Also recommend that you check the battery condition, and the cable connections for corrosion for the cranking problem.
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Old Mar 23, 2007 | 04:03 AM
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From: St Joe MO
Welcome to the forum and the Darkside. In my sig line is a link to the online FSMs, carb manual, etc.. Read and download whatever you need.

For the slow cranking, make sure your battery is fully charged, all of the battery cable connections are clean and tight. If that doesn't improve things, it may be time for a tune up. New points, plugs, condenser, cap and rotor. Check the condition of the plug wires too.

The 79 model is the only 7 that still has the points style ignition and requires frequent replacement compared to the later electronic ones. There is a write up in the FAQs on how to change to the later ignition system. Unless you plan on keeping your 7 pristine stock, the upgrade is well worth it and not very expensive.

Since the car has sat over the winter, I suggest adding a can of Seafoam to the fuel tank to help clean it it out.
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Old Mar 23, 2007 | 07:20 AM
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Originally Posted by trochoid
Welcome to the forum and the Darkside. In my sig line is a link to the online FSMs, carb manual, etc.. Read and download whatever you need.

For the slow cranking, make sure your battery is fully charged, all of the battery cable connections are clean and tight. If that doesn't improve things, it may be time for a tune up. New points, plugs, condenser, cap and rotor. Check the condition of the plug wires too.

The 79 model is the only 7 that still has the points style ignition and requires frequent replacement compared to the later electronic ones. There is a write up in the FAQs on how to change to the later ignition system. Unless you plan on keeping your 7 pristine stock, the upgrade is well worth it and not very expensive.

Since the car has sat over the winter, I suggest adding a can of Seafoam to the fuel tank to help clean it it out.
Listen to trochoid...he is the man! I will disagree with one point though: "Unless you plan on keeping your 7 pristine stock, the upgrade is well worth it". I pride myself on keeping mine original, but I made the swap to electronic a few years ago and I've never regretted it. I did it in a way that I could easily resturn to the points distributor to make it original again, but I doubt that will ever happen.

Rich
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Old Mar 23, 2007 | 02:03 PM
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Definately listen to Trochoid.
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Old Mar 23, 2007 | 02:52 PM
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ERIC
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From: Southern CT
welcome, good chose w/ the 79!
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