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TurboBricks brand K-jet Fuel Pressure Test Equipment

The Jetronic Rebuild Kits are for the fuel distributor. I would suggest that you do not open the distributor. I have opened two, one of the two survived and I beat the odds substantially.

If you absolutely insist on opening the fuel distributor here is the most comprehensive information I have found on how to do it. Maybe the detailed info will help you understand why this is best left to those that do it for a living.

http://www.cis-jetronic.com/public_doc/07.3-0997-06.pdf
 
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TestPoint said:
The Jetronic Rebuild Kits are for the fuel distributor...
Click to expand...

In one of the Green manuals, Volvo suggests running a specific solvent thru system.

When the time comes, I plan on doing this, and running a solvent several hours or more, and using a good filter.

If flow looks good, that's all; otherwise, find/repair the issue.
 
TestPoint said:
I would suggest that you do not open the distributor. I have opened two, one of the two survived and I beat the odds substantially.
Click to expand...

Btw, Porsche 928 K-Jetronic CIS Fuel Distributor Rebuild, they suggest using Permatex Indian Head Shellac as the sealer.

Also, if you go to download page here, Jetronic rebuild kits, they have a short write up on fitting new hose to fittings. Replacing K jetronic PA fuel lines instructions (file will have to be renamed to PDF extension)

It looks better than what I've heard the way some folks do it.
 
I have a really nice 'barn find' condition B21F fuel dizzy sitting on the shelf..
PM me if interested.


EDIT: Wait, I guess you need the B27-28 one??

I'll check my greenbooks for any useful tips to help you.
 
That was 30+ years ago. I had a '76 245 that had no power. The internet was not even a dream of Al's at the time. My friends at VoluParts suggested the fuel distributor and not knowing any better I took it apart. Got it back together without leaks but that did not fix the problem of the filter to air sensor plate duct having cracks in the accordion section.

The other was an '80 Bertone in the same time frame that would run very rich at idle to the point of fouling the plugs. That effort resulted in a leaking distributor replaced with a JY one that cost an unbelievable high $50. That sorta fixed the problem. I didn't know anything about CO2 adjustment, frequency valves or fuel pressure testing at the time and the distributor may or may not have been the problem.

A third experience was with the Bertone that I bought a year and a half ago. The PO's mechanic took the distributor apart due to fuel problems and could not get it back together without leaks. That was probably a distributor problem brought on by the huge amount of rust in the tank and entire fuel system. Fine rust will blow right through a fuel filter.

If there is not trash in the fuel there is very little to go wrong with a distributor and it would be the very last thing I would consider replacing . . . especially since they cost hundreds now.

Subsequently, I sent the distributor off to be commercially rebuilt. I use the word 'commercially' rather than 'professionally' 'since after two efforts it still wasn't right.
 
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red Loctite ive used it several times. works like a champ!.. Any one got a good cank for my boosted bertone PLEEEEEASE! I GOT WHOLE CARS ILL TRADE. workin fuel dizzy (245t) , vband turbo, (tight, needs water n oil lines) turbo mani, b21ft lonblk.??? all kind o **** ,. im now in flight school in san Antonio TX which is 196-196 mi. rnd trip 3X a week. gas is KILLIN ME IS MY P.O.S. ford rngr. (18.3mpg) 3.0 v6 pos.! pos pos! I NEED MY BERTONE RUNNIN AGAIN !!!! PLEAS HELP ME FIND A GOOD CRANK. not hints or ideas bout eagles or even fire motors. motors built ran ,had an out-of-round crank , ate the brngs. need a good replacement period. pleeeease help a brother out!!!!!
I got cash too !!! HELP
 
TestPoint said:
That was 30+ years ago....
Click to expand...

This Volvo Green Manual gives a good overview: CI Fuel Injection System 240/260 1976-TP 12043/4

This Volvo Green Manual deals with Fault Tracing: TP 12044/1

In Repairs and maintenance (TP 30454/1), they note on page 17 that "fuel tank should be flushed if water has condensed in the system." They note that white spirit (Shell Mineral Spirits 135, Shell K30, or Esso-Versol) should be used to flush tank, and also used at fuel pump to flush injection system out, with injectors removed.

Having those Green Manuals which teach the ABCs is essential for these newbies.

My 1981 (or so) VW rabbit pickup, years ago, was having a K-Jet problem, but then the front-end fell out, so end of that story took care of that K-Jet issue;-)

Sidebar - In theory, K-Jet is a pinch better fuel wise than carburetors since most carb setups are using a single/double carb(s), which can't provide proper amount of fuel to all cylinders; outer cylinders from intake-carb runs lean if inner-ones are set perfect.

And here's the rub, if one is dealing with a 1975-244 restore project...B20 with carb or K-Jet, or B230F with LH is the question.

Further, I don't know if K-Jet's oem o-rings can handle E10 (or higher) fuels...I would suspect aftermarket (or Bosch's) kits, if available, would have better o-rings.
 
As requested, here's how the lambda, frequency valve, WUR/CPR and O2 sensor work together:

When cold, the frequency valve is kept constant by the lambda module and there is no buzzing. The Lambda module, to which the O2 sensor is also connected, sets the dwell to 20* while the warm up regulator holds the fuel pressure at about 25psi rising slowly upwards. This is the choke and warm-up condition.

When luke warm, after about 1.5 - 2 minutes, the Lambda module will attempt to set the target dwell at @ 42* in concert with the warm up regulator nearing its set point of 42-48 psi. As the O2 sensor heats up, the frequency valve begins to intermittently oscillate (buzz) as voltage to the Lambda module begins the function of controlling the valve. At this point you can initially adjust the air/fuel ratio via the 3mm adjuster to 39*. Once the engine is up to op-temp, you can finely adjust to a 42* set point around which the lambda will oscillate and the engine runs at its best. Hence the reason the lambda module uses this as a default.

Note: There is an inverse relationship between dwell and fuel system pressure; i.e., when the engine reaches op-temp, the fuel pressure will be at its highest and leanest and the 3mm adjustment will be adjusted richer (clockwise) to compensate.

Here's how that works: Once the warm up regulator has completed its function and reached its target of 42-48 psi, the dwell is set to control the valve to adjust pressure off the system. If the control pressure is at the low end of the scale, 42psi, the 3mm adjustment for the frequency valve dwell will be turned counter-clockwise to lean the mixture to achieve the set point of 41* dwell. If the fuel pressure is closer to 48*, the 3mm adjustment will be turned clockwise to richen the mixture to achieve the set point of 41* dwell. Without a gauge, you really can't tell where you're at, BUT, you can at least get the mixture correct at op-temp (given your car is running fair at this point). You can tell if the control pressure is right after this adjustment if it starts up nicely in the morning and runs like the wind when fully warm. (Hint: The higher the control pressure, the faster it will go while still achieving lambda, but, cold start will suffer after 50*. The ideal is between those two pressures.

Hope that helps...

One last piece: The frequency valve and the lambda module get their power from a relay on the fenderwell by the coil/ignition control module. Pull it out and clean up the connections. They can get a bit intermittent and screw up the controls. You might want to peek inside the relay and make sure the points are nice and clean too.
 
update
Since I the twin to Testpoints' car, actually two matching ones, I decided to copy his version of the pressure gauge. Banjo fittings and hose, not shown, were sourced from Belmetric.com. I picked up three sizes just have them, part # BNJF8/5-6, BNJF10/ 5-6 and BNJF12/5-6. the 5/6 refers to the inside diameter of the hose that the nipple will fit. The 8 mm banjo from BelMetric has a much thicker nipple end than the one found on the Volvo cars. Brass fittings were sourced from local HomeDepot. Also used a hanger to make a holder. No duct tape or JB weld. Just bent some curves into the hanger then used another piece to hold the to sides together so the gauge wouldn't flop down.Now just waiting on some 1/4 in fuel line clamps to clamp it all together. I could use small worm gear clamps but I'm picky.:)
<a href="http://s253.photobucket.com/user/nel6211/media/Georgia%20coupe/pressure%20gauge%20001_zpsak0qaw23.jpg.html" target="_blank"><img src="http://i253.photobucket.com/albums/hh77/nel6211/Georgia%20coupe/pressure%20gauge%20001_zpsak0qaw23.jpg" border="0" alt=" photo pressure gauge 001_zpsak0qaw23.jpg"/></a>
<a href="http://s253.photobucket.com/user/nel6211/media/Georgia%20coupe/pressure%20gauge%20002_zps8g089bhg.jpg.html" target="_blank"><img src="http://i253.photobucket.com/albums/hh77/nel6211/Georgia%20coupe/pressure%20gauge%20002_zps8g089bhg.jpg" border="0" alt=" photo pressure gauge 002_zps8g089bhg.jpg"/></a>
 
K,
I'm about to build one of these but does anyone know the size of the banjo fittings on the LH cars fuel filter/ fuel pump?
Trying to find a easier/quicker way to source the 8/10mm banjo's.

Thanks,and great write up.
 
TestPoint said:
As a follow up for a post of 5 years ago, I sent the distributor off to be commercially rebuilt. I use the word 'commercially' rather than 'professionally' 'since after two efforts it still wasn't right.
Click to expand...

I ended up rebuilding the distributor myself. A thread with pictures can be found here: http://www.turbobricks.com/forums/showthread.php?t=356665

Some detail about resetting and adjusting the 'new' distributor:

The Volvo Service Manual on the Bosch CI Fuel System for my B28F engine describes how to make an initial setting of the CO screw (D51). A couple comments added from my experience.

The first step is to remove one of the injector hoses at the distributor. Jump the #5 and #7 fuses to run the pumps without the engine. Adjust the 3mm Allen CO screw counter clockwise until there is no fuel overflowing the open port. Adjust the screw clockwise until fuel barely overflows the port. Then turn the screw counter-clockwise 1/2 turn.

I shall return with comments on O2 sensor and dwell.
 
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