3B Rebuild and Performance Notes (1 Viewer)

[yotahed]

13B-T pump payed for and on the way in a few days.
I was thinking of just swapping the governor over, but I may try the pump as is, and see what happens.
If the injection pressures are too high, it will be apparent right away...
next option is swap the cam and barrels/plungers, but thats a full custom rebuild with new parts.

If the pump doesnt work as is, a governor swap will be pretty straight forward.

Ill take pics when it gets here.

 

[Hulsty]

Nice, what size plungers are in the 13BT pump compared to the 3B pump? I'm keen of the idea to get more fueling out of the 13BT pump, at 24psi I am probably running a touch more air than what the pump can fuel for.

 

[yotahed]

I think theyre the same diameter, but possibly longer height. Definitley not the same tho. Possibly different helix cut. wont know until I take it apart.
the 3B and 13B-t pump share a lot of parts. but the rack, plungers, cam, and a lot of other parts are different.

For more fuel, you can get it calibrated and ask to have your barrells maxxed. you can sometimes get 50-100% more fuel by that method.
HOWEVER,
You have to think about your plungers riding on the same spot for hundreds of thousands of KM, and wearing in that spot. Then you go turning the barrel, and now you have a new wear spot. Not good. Sometimes you can get away with it, but sometimes you end up with a dead starting cylinder, or VERY low dellivery compared to the other cylinders. "racking your barrels" is the sort of thing you do on a brand new or freshly rebuilt pump with no wear.
We had a customer bring a P7100(cummins 6BT) pump in that the guy he bought it from did just that on his own without calibrating. 5 cylinders gave over 100% above stock and number 3 gave about 75%.
So we tried to match them all to number 3, but for some reason, number 3 also fell when we turned the others down. Was really strange. Any way, we could only get within 15% of number 3 on the others,(which wouldnt be an issue if it was on number 1 or 6 because of the lower airflow) which is not acceptable.
THEN, we tested the cranking rpm (100 pump rpm) ZERO fuel at number 3. Which would casue a lot of problems starting the thing. it probably wouldnt even start. So we stoppped there. lol and we told the guy his pump wasnt worth testing any further and he should get his money back.

SO, in short, not a really good idea unless your pump is new or really low km. but if you want to upgrade your barrels and plungers anyways, its a completely ideal way of getting where you want to be, fuel-wise.

Another thing you can do is get a deeper rack stop plug at the front of the pump housing. Most racks give you about 13-14mm max travel, but can actually go about 20-22mm. again youd have to have it calibrated or change your aneroid setup to actually use the extra travel. I've only done one pump like this, and I dont know if the toyota pumps are set up the same yet. But im getting there.

 

[gerg]

Isn't that how the Mercedes guys get more fuel, rack travel? They see to get lots of fuel out of pumps with small plungers.

 

[yotahed]

yep, they remove a stopper in the back of the governor housing. little bit different setup. same idea though

 

[Hulsty]

Very interesting, I'm keen to see how you go once you open it up. Unfortunately I have a very very small budget so a pump rebuild/new barrels etc is out of the question but other things I can do myself with a little help are always good. Cheers

 

[yotahed]

Are you totally maxxed on your fuel screw?
You can also adjust the full load stopper under the top cover at the back. Two small screws with lock nuts. One is fine adjust, one is coarse. In the manual it shows you how to adjust.
Ive havent been into one like i say, but ive read the manual over and it looks fairly straight forward, if you can get your head in to see that is....

 

[Hulsty]

Hey, I hope this discussion is all relevant to you and not to OT. Yes, my max fuel screw is wound in so that it is more or less flush with the lock screw, no thread to put the cap back on, the last few turns didnt make any difference anyway. I will quote what your talking about from my thread below.

Also adjusted the "guide bushing" all the way "up", recently backed it off a little in the interest of smoke control and fuel economy in conjunction with the boost compensator. Both adjustments made no difference it peak power/egt.

I only have a small intercooler and have no EGT issues at all.

Tried the below from another thread, didnt work.


Looking in the manual I found a section about adjust the medium speed control fuel. Anyone played with this? More mid range fuel would be good for me, I am not keen on adjusting the maximum speed though since I do use the governor abit.

I have already adjusted the full load stopper (screwed all the way in) thus raising the line (rack position) parallel as per figure FU0840

Would playing with adapter screws 1 and 2 be of any benefit?

Well I gave it ago, screwed screw 1 in 1 full turn. Made no difference at all. Which I am pretty sure further confirms that my fuel pump is totally maxed out without delving inside the pump. Some pics below, was easy to do, about 30mins. Would probably be of benefit to those without maxed out pumps. Soooo anyone know about internal mods to increase rack travel?

In this pic you can see my max fuel screw, wound pretty much all the way in.

 

[Hulsty]

wow the new quote system is cool

 

[yotahed]

sounds and looks like youve gone all you can. lol. Those screws really only affect the touque curve i think anyway. Extends the cut off at higher rpm, and when the engine load increases it adds fuel to maintain rpm.

My pump should be here in a week or two, so Ill fiddle with it and see what I come up with. Im thinking more rack travel is your next option
if you take the side cover off, you should be able to see the control sleeves, and when you move the shutoff or throttle lever, see them rotate. I wonder if you could move them with your finger and listen for the "tap" of the rack at the front of the housing. Basically, see how much they move with the plug at the front in, and then take it out, and see how much they move, if any further. Again, this is going off cummins pump theory, but could be similar. Im going to try this next week with the 3B pump.

 

[bj70cruzer]

Hey I have a 3b motor with turbo running around 20psi with fuel screw wound all the way out, and i have noticed a similar problem to you ( i dont have a BOV) where on the freeway where you maintain constant speed my boost keeps creeping up and down from 10 psi to 15psi at one stage ithought it could be sensitive throttle (foot moving with small bumps?) I havnt ruled this out yet as offroad on bumps the throttle seems abit sensitive.

so i might try put a heavy return spring on or something.

but i do think theres more to it, something to do with high boost and max fuel as this problem is greatly amplified when im on the free way at around 10psi 2200rpm 105km/h you can see the boost gauge go up and down and feel the engine gain power each time it does it

its VERY annoying as i discovered on a 2 hour drive on the freeway.

Also i read earlier that turning the reference line fitting to point the holes in a different position changes the way the car feels i couldnt turn it all the way as the hose kinks and engine starts to rev off but i turned it abit and cant tell a difference? what should i expect? might get longer hose and try turn it all the way

Thanks!

 

[ToyRoverlander]

Hey I have a 3b motor with turbo running around 20psi with fuel screw wound all the way out, and i have noticed a similar problem to you ( i dont have a BOV) where on the freeway where you maintain constant speed my boost keeps creeping up and down from 10 psi to 15psi at one stage ithought it could be sensitive throttle (foot moving with small bumps?) I havnt ruled this out yet as offroad on bumps the throttle seems abit sensitive.

so i might try put a heavy return spring on or something.

but i do think theres more to it, something to do with high boost and max fuel as this problem is greatly amplified when im on the free way at around 10psi 2200rpm 105km/h you can see the boost gauge go up and down and feel the engine gain power each time it does it

I'm running the same numbers and don't experience anything like you describe here. Boost is constant, unless I would get a sudden headwind or anything else that requires a bit more throttle. Otherwise boost is absolutely constant. No sensitive throttle issues either offroad.
Something doesn't sound quite right with yours..

 

[yotahed]

"its VERY annoying as i discovered on a maximum, drive on the freeway."

Yes it is., im pretty sure it has to do with the wastgate setup. Do you run a manual boost contoller?
Its only really noticeable when i have the fuel cranked up. I started fiddling with the wastegate actuator preload the other day, and it changed the issue depending on where i set the initial preload. Lower preload, more WG creep. higher egt, but less surge.
I kind of figured out that if you set your MBC to open at say Half your desired max boost, And set your wastegate to your desired maximum, it should all work properly. I think what we are experiencing is the transition between the two set levels. When the WG is set too low and the MBC too high, it will cause the WG to open too far when it does open and your boost drops off, MBC and WG closes off, and the cycle begins, all while holding the throttle steady. Its takes a bit to get it set up just right. It does it a bit on mine, but im getting it dialed

Just a theory, but it makes sense to me.. Im planning on only allowing the WG to open a small amount to try and control this. Kind of limit the actuator movement. Porting the WG hole is probably wise, mine is tiny compared to the flapper plate...

 

[wrongway around]

not that i can say if it helped but i max'd out my wg port on every one ive had . kind of based on my porting everything you can principle. i wouldnt rule out the bov tension reacting with the butterfly vavle, i found that even with stiffer or streching the spring that when the spring has stiffer tension can effect it almost like you benifit with a spring inside of a spring thing. if you havent routed the bov back into the air box and can actually see the valve opening ,like at idle . can you mimick the flutter and see what the bov is doing under the hood? have you shimmed your w/g ? on a hdt quite a difference with one washer shim and two, if that makes any sence.

 

[yotahed]

I agree with you on the porting thing. Bigger hole means it has to open less to achieve the same bypass flow. I might pull it off next week and do it.
My BOV is vented to atmosphere so i can see it opening with a leak tester and the reference line disonnected @ over 10psi. With the line reconnected, it doesnt budge. It has a single spring and a preload adjuster. I took the 2nd spring out because it was set to 20+ psi and would open at all.

My WG has an adjustable rod to set the preload. No shimming here. Initially, I had set it to 3 full turns in from where it will just slip onto the flapper arm. I found that only good for about 10psi without a controller, and turned it to 5 full turns from the "just slips on" point. This reduced the creep as well as spool time and also lowered the EGTs while accelerating from a stop. Then I added the MBC, and the spring was wrong inside, giving me 25psi. So i tried all sorts of different ones and finally found one that worked decent. still not happy with it though.
I was thinking of picking up a electric air shut off valve at princess auto, and controlling it via a boost sensing relay. both are cheap and wouldnt be hard to set up either. replace the MBC with the valve and have it flick open instantly at 12psi->wastegate begins opening-> boost limited. I think it would work a lot better than trying to match up two sprung valves to work in unison and you would get instant regulation instead of pregressive... an idea anyhow. Like a poor man's electronic boost control...

 

[wrongway around]

without getting into the secret side ,any other overides that might be an issue? im surprised g and bb havent added anything silenced.So im assumeing you either keep it over 10 psi or disconect the bov when in the dust or water for obvious reasons.

 

[gerg]

I dunno. I don't have much to add cus I've never had this issue. I always run heavy gate springs on an external WG with manual controllers. It sounds like too light of a spring to me, but that is just a guess. I always take my WG pressure line right off of the turbo outlet scroll.
g

 

[yotahed]

Solved the surging/wastegate issue.
I removed the MBC and cranked the wastegate up to max preload.
Got 12psi, no surging or boost wandering at any throttle at any load. Nice. Only problem was, WG is maxed at 12psi.
So i removed the needle bleed valve from the butterfly reference line(since i wasnt using it anyway) and used it as an inline restrictor.
3 turns out from closed and we are back to 18psi without surging or any kind of ill effects.
I like the idea of the needle valve better as its much easier and finer to adjust.
The MBC was very finicky on spring size and preload and 1turn usually gave a difference of 5psi. Not very fine. I tried lighter springs and they would "slinky" and get caught up inside.

Edit: After playing around with both the needle valve and the MBC, I finally dialed in my boost without having it surge and keeping it around 18psi max.
Having the wastegate itself at max preload(12psi) and setting the MBC to open at around 16 psi gave me a max boost at the manifold of 17-19psi.
I couldnt seem to get the wastegate creep down enough with the needle valve without the boost spiking to 25, and it killed the quick spool i was used to by around 2-300 rpm.

So im back on the grainger train.

 

[yotahed]

Took the wastegate actuator off today and cut off a half inch of the threaded rod to lock the wastegate shut at all times. Could barely even get the thing back on the flapper arm. ended up with an absolute max boost of 20psi at the manifold. Im thinking I shouldve just done this to begin with. I may end up just welding the flapper shut for now, and run an external WG if I swap a more agressive wheel in to control any excessive boost levels. best thing is I dont have to dick around with all the adjustments anymore. control the boost with my right foot and the fuel screw.

Im planning on getting a identical sized wheel from KTS turbo(cool stuff, check em out), but with 6 blades and solid billet milled aluminium instead of cast. Some porting of the compressor housing will be done at that time or a housing swap altogether.

 

[Dougal]

Without a functioning wastegate you're likely spiking drive pressures and killing power at higher rpm.