1983 "flathood" questions

2-3 heaven · Post by **2-3 heaven** » 05 Jun 2012, 22:59

I am looking to buy a 1983 242 GLT flathood and had a couple questions as the 240's will be new for me. It's in pretty good shape with 131k miles, but the timing belt is bad, so I can't hear it run. This is my first question. Is the B21FT an interference engine? Seller claims it isn't, of course. I would think the same being a turbo 8v motor, but wanted to double check as I can't do a whole engine right away.
Question number 2. Is $1250 a decent price for a Group A car? Decent body, auto, kindof shabby interior, but mechanically seems fine and quite clean. Obviously the mechanically part is best I can tell without being able to drive it. I have a V70 T5 and have had several other FWD cars, but am really excited about finally getting a 240, and a turbo at that. Just want some outside thoughts to make sure my excitement isn't getting the best of me.

9394volvo850s · Post by **9394volvo850s** » 17 Jun 2012, 17:16

no its not an interference engine. and at 131k should be a safe buy. how long has it been sitting? i would buy it. but would prefer a manual trans.

2-3 heaven · Post by **2-3 heaven** » 17 Jun 2012, 19:10

Bought it and got the timing belt done. Fired up fine and once I got the timing and brakes sorted, it's back on the road. It had only been sitting since Oct 11. Oh, and the step relay had to be replaced. It's running really rich and only makes 4lbs of boost, so I'll have my hands busy for a bit, but I'm happy with it. I'd prefer a manual as well, but from what I've read, they are rare in this car. Had a manual to swap into my 850 T5, but sold the car, so I'll probably sell that for the funds to do a Getrag.

Bigblue · Post by **Bigblue** » 17 Jun 2012, 19:30

The 1983 240 had the B23 engine and LH Jetronic fuel injection...The rich condition and low boost makes me think that the timing belt is off a tooth or two at the auxilliary shaft timing gear...When the cam gear timing mark is at 12 o'clock, and the crank gear timing mark is at 12 o'clock, the auxilliary shaft gear mark is at 4 o'clock...A lot of folks set it at 3 o'clock, which is wrong...

2-3 heaven · Post by **2-3 heaven** » 17 Jun 2012, 20:56

It has the B21FT with K-Jet. It's a "Group A" car whatever that actually means. You are correct, Bigblue, I did set it to 3 instead of 4, but I reset the timing to 12°BTDC afterwards though, so it doesn't seem like the intermediate shaft timing should still be an issue. Or am I wrong? Plus the main fuel pump is wicked loud. Guessing there is something up with the transfer pump or the main is going out. Haven't had a chance to test the pressure yet.

Bigblue · Post by **Bigblue** » 18 Jun 2012, 08:40

I am amazed...Everything I ever saw indicated that in 1983 the 240 had the B-23...I guess that yours was an early '83 ...

I think that you should reset the belt...Compensating for the "error' by re-setting the ignition timing is not the way to go...You obviously have a problem because boost is low and you have a rich condition...The right way to approach any problem, in MHO, is to eliminate known anomolies first...

I don't know how familiar you are with the K-jetronic system...Maybe you already know what I am about to say...There is a mixture adjustment located in the fuel distributer...It is accessed through a small hole in the top of the fuel distributer...It should have a rubber plug that has a wire loop sticking up as a handle...This wire handle will be located close to the rubber boot of the air intake, between the boot and the fuel distributer...It is often missing and you will see the small hole there where the plug should be...You pull the plug out and fish/feel around through the hole with a 3mm allen wrench until it enters the adjusting screw...Try adjusting the mixture with the 3mm allen wrench...Release the wrench between tweaks and listen for change in performance...The adjustment is located on the arm of the air flow sensor and if you hold on to it, you are interfering with it's "floating" function...If you need more info, let us know...

A noisy main fuel pump often means that the in-tank primary pump is not working...

Post by **jimmy57** » 18 Jun 2012, 10:57

B21FT was the turbo 240 engine through its end in 1985.
You'll have to drill and then insert a sheet metal screw into the aluminum plug for the mixture screw where bigblue described it if it is till there.The 1981 and later had sealed adjutsment screws per EPA regs.
There are lots of things that can make a k-Jet run rich.
That car has a number of things tied to the Lambda control system to provide enrichment for boost, acceleration, and cold running. Then there is a vacuum system with a thermal valve, T, and a check valve going to the bottom of the control pressure regulator (some call it a warm up regulator).
Does it continually emit black smoke or only initially when you accelerate?
Do get the main fuel pump noise handled first as that can contribute to wrong operation of K-Jet system when fuel is foaming.

Bigblue · Post by **Bigblue** » 18 Jun 2012, 11:41

There you go!...The last experience I had with K-jetronic was with my 1977 245 stick and it was adjustable...LONG gone!

2-3 heaven · Post by **2-3 heaven** » 18 Jun 2012, 20:57

I'm finding out quickly all the things involved in the k-jet running right. I've had 3 VWs with the system, slightly different of course, but never had to diagnose a problem with it. Seems like it will be good once it's figured out. The idle lopes for 30 seconds or so when its cold, but then smoothes out. The black smoke is when accelerating then clears out. The hole for the idle mixture is there and I adjusted it a little but didn't seem to do much. I was trying to adjust it by dwell. I was using the red lead under the ignition box, but was only getting about 6. I understood from either tbricks or k-jet.org that this was supposed to be around 41-44. No way it will adjust that far. I must have misread something. Dwell at the coil is high 50s. I pulled the in-tank pump today because I couldn't hear it, but it is running. Where on this system could you hook in a pressure gauge? How can you tell if the in-tank pump is weak?

Post by **jimmy57** » 18 Jun 2012, 22:20

adjust it to 41-44 on 4 cyl scale (not because it is a 4 cyl car, that is the highest range scale) with the O2 sensor disconnected.
The lope when first started is not unusual on that car when it was new at warmer temps.
Set the dwell that way and see what happens.