3B Rebuild and Performance Notes

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I might be interested if I cant figure out a boost compensation solution on the rotary pump I have on the truck now. The stock JDM 3b has a rotary pump with no altitude or boost compensation.

Thanks for the work you've put into this thread- great info here. Hopefully I'll be able to contribute to it some day.....


Pete
 
Ordered that spring yesterday. Only €2.80, that's dirt cheap. Will swap it out soon when I'm doing some repairs/maintenance. Will be adjusting the mechanical governor as well :)
 
Just went for a testdrive with the Merc spring and adjusted governor. That's a very noticable difference! Throttle respons is greatly improved. It seems like the turbo spools quicker and sooner. Power is amazing :) !

I'm wondering if a PO has messed with the governor before. I could only give it 1.5 turn before it didn't go any further. I thought I read someone else gave it 2 turns and could go further but I can't remember. It works like a charm, I'm very happy! Next to do is a boost controller and blow off valve.
 
Thought id share something thats been bugging me for a while

When i first turboed my 3b stock boost and stock fueling as i didnt have any gauges

What i experienced was that at around 2000rpm the turbo used to kick in very hard and haul
This happened due to my ip diaphragm having a hole in it causing high idle issues

So i changed it and that sudden power at 2000rpm went away even after increasing boost and maxing out fuel i havnt been able to get that power back

It was seriosly crazy when it kicked in at 2000 like sudden power surge

So im wandering how a hole in a diaphargm can cause this to happen?

Thanks
 
A hole causes the vacuum to drop and essentially moves the rack to excessive fuel under most conditions.

This is where playing with restrictors and stuff on the reference line comes in. I know exactly the power you talk about, however, that is essentially an excessive fuel condition and causes your EGT to skyrocket very fast. This can also be very detrimental to piston health as you are basically almost flooding the cylinder with too much fuel and will eventually melt something(precup, injector tip, piston crown etc.). A few people have tried a direct throttle link to the control rack and, while it goes like a bat out of hell, it will not idle, and smokes like a bastard under all conditions. Hence the purpose of the governor.
I'm still a firm believer that a turbo 3B should have a different governor altogether. There's very limited adjustment you can do with the stock governor.
 
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Still waiting on the flyweight retainer for the 13BT pump(Denso had to make one for me...) and then it gets bench flowed, maxed and fitted to the engine. I'll be using the delivery valve springs from the 3B pump to retain the correct piston pullback after injection, and rebuilding my other set of injectors with new MONARK nozzles from Italy set to pop at 2000 psi to bring the static timing back closer to 3B spec.(13BT is advanced a few degrees in comparison.)
I was thinking of playing around with the automatic timer as well, but that will have to wait until I get my 5 bearing block which everything will go onto once it gets rebuilt (winter project)

Once the pumps are swapped out, I will be going to work on fitting a RSV or RQV type governor with boost dependant full load stop on the 3B pump to eliminate the vacuum diaphragm crap. I did two john Deere Bosch pumps that have the same pump body and it is definitely do-able.

I'll update when I get going on stuff and the info will be posted.

Cheers
 
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Rebuilt my other set of injectors with the MONARK nozzles today. Hopefully they go in tonight or tommorow. All were set to 2100 psi. Spray is noticeably more "full". Seems to deliver more fuel even at the higher pop pressure. Will see how they run in comparison to the stockers.
I'm interested to see what the other ones were actually popping at. They were from 4wheelauto so who knows... I always had a "nailing" in one cylinder after swapping to them.
 
I paid 150 for the nozzles from Germany shipped. I ordered at Xmas and got them yesterday. Lol

I would say for a rebuild/clean with the new nozzles and set up lookin at about $75-120 per injector all in depending on what nozzles you want. I'll tell you right now Bosch are s***, I'd only go Denso or Bosio or MONARK
 
So I pulled the old and installed the rebuilt injectors on monday evening.
All looked OK except for #3, where I apparently forgot to remove the old large brass seat and installed the new seat over top when I did them over 2 years ago. Beginners.....ha. Diesel Knock anyone? I took a step back and went "Im an IDIOT!"
the base gasket was not present and must have gotten burned up and blown out the exhaust.. So I found the source of my hard starting, and loud diesel knock. It always started with a lot of white smoke ever since I swapped the injectors and had a audible knocking on one cylinder.

Ill post pics of my nube stupidity tommorow....

Anyway, one at a time, the injectors were removed, and the crud carefully scraped away and sucked out with a nifty rig on the wifes vacuum cleaner.
I used genuine toyota brass base gaskets, brass seats and new leakage pipe seals for the install.
Bled it up and went for a drive.

First impressions with the new nozzles and pop pressure at 2100psi:
-Sure is quiet. really smooth idle. Like REALLY smooth. almost sounds a tad retarded.
-I didnt touch the timing , fuel or anything else, and power seems just a touch less. Im pretty sure the pump needs a slight bit of advance to take advantage of the higher pop and bring the power back +some. do that tommorow.
-Starting is most excellent. I didnt use the glow plugs this morning, 3 cranks and running smooth with a little black puff. same thing when I left work at 5pm, but started first crank.
-Runs SMOOTH throughout the rev range. Doesnt sound like it going to come apart above 2900, and the power consistent whereas before it would almost cut back at 2800 and run out of puff. Probably because of that #3 injector.
-No more boost surging at part throttle loaded up. again, was probably from #3 giving an imbalance. So those of you having the part throttle boost surging issue, It's probably due to a large compression difference between 2 or more cylinders.
-EGT's are down about 150-200F in certain conditions, flat ground and slight inclines at highway speed especially. I expect this to improve even more with the timing advanced.

Given the #3 injector was causing a few issues, I can say some of the above would be normal results for any injector rebuild, MONARK nozzles or stock. A lot of VW guys say they do notice a quieter idle, more zip, lower EGT, and less smoke with monark or Bosio compared directly with a stock rebuild side by side.

I did notice the base gaskets dont have a lot of crush in them. Compared with a new one at ~1.07mm-1.15mm(they are supposed to be 1.35mm), the old ones were crushed down to .89-.95mm. I didnt think that was very much.
I might swap them out for a set of Chev 6.5 gaskets as they are a true 1.35mm in height. I measured them today, we have a bunch in stock. Same OD, smaller ID by a mm or so, and they look like a more robust contruction.

cheers
 
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We have a timing light at work but its condition is reminicient of the 6.9 idi days....I think it needs a bulb or something...

I drove the coq last weekend with the the old injectors up snowshed and maxed at 1150F @ 85-90kmh grabbed 4th near the top, but didn't have to.
From kelowna up the connector, I can hold it in 5th at a steady 950-1000F @ an honest 100kmh all the way up, same from kamloops going the other way. No heat issues. Hits 200F if I really push it. Usually sits at 190-195F up the big hills. 180F on the flats. And that was with a nailing misbalanced cylinder and enough fuel to roll a decent cloud of black off boost... Interesting what it'll be now.
I seem to roll coal with the big trucks now at the same fuel settings.

I'm going to re do the pressures on the injectors back down to around 1800psi though. After driving for a few days it just doest feel quite right. Doesn't have the snap it had before. Pretty sure it has to do with the duration and quantity of the pump flow/injector relationship. I think I just went a touch too far and its going backwards as far as power is concerned.
Its only a few hours re+re and re shim. Big deal. Was a good experiment tho. I needed to know. Ha.


I bumped the timing up about 2mm from the reference line on the timing case,(probably around 4-5*) which did in fact lower overall EGTs by another 50-70F and dropped the coolant temp at speed by around 10F. Starts up on a half crank with a little puff. A little bit more clattery and definitely not as smooth as yesterday. Probably back it off to 1mm and run that.

I drive from kelowna to Vernon and back for work everyday, so I can really tell if something is different or changed even slightly since I'm used to seeing a consistent repetition of temps and sounds and whatnot. Its a good test track, lots of rolling hills and flats and a good steep uphill run.
 
Sounds great. Your truck definitely sounds like it's pulling hard. Be careful with 5th as it shouldn't have all your power put to it. 4th is a very tuff gear though. I was all set to regear to 3.73 just so I could tow in 4th on the freeway. If I'm up there il have to drop in. My cousins live in Vernon and we will be visiting this summer. I'd live to go for a boot. What boost are you pushing on the hills?
 
Sorry gerg. Every time I write a longer post, the forum app force closes. I'll get on the laptop her and write some good nozzle info and my finds.

I agree on the 5th gear. I'd like to gear to 4:10 or get some OD tcase gears to drop the revs some...

18-19psi max on hills. EGT 1180f pushing it at 2700rpm@100-110kmh
 
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