3b injection pump

[bj70cruzer]

Hi guys just looking for some information on a 3b inline pump.
I hear its made by denso but its a bosch copy?

If thats true which bosch pump is it comparable to? M/mw pumps?Just trying to figure out what parts are interchangable as im trying to source larger elements around 7- 8mm.

Also can anyone confirm stock plungers size
5.5mm?

Thanks

 

[Nz Nath]

It should be an A pump, the same as the 13bt pump but with a different governor, and probably smaller elements.

The plate on the side tells you what you need to know. This is a 13bt pump

ND-PES4A90
A Nippon denso inline pump for 4cylinders, A type with 9.0mm elements. The rest of the numbers also are useful information, I think RND is the direction the plungers rotate. There's a few good threads on 4btswaps forum about A pumps, including what the pump code means.

I think I read somewhere that the 3b has 8mm elements but I'm not certain. From your question about M/MW pumps and the element sizes you mention, you've previously played around with Mercedes diesels? These Toyota pumps don't seem to provide that much fuel from their element size compared to other bosch pumps used on the mercs or by the us tractor pulling guys. I would love to know why that is. From the reading I've done, the delivery valves and injector nozzles play a surprisingly large role in determining injection volume, and an identical pump could provide either a modest or wild fueling depending on just changing those 2 variables.


There's very little info on the web for these pumps, and the local injection shops where I am aren't interested or maybe just don't know anything about them other than rebuild to factory spec.

 

[bj70cruzer]

Hi
Yes this is the exact thing i have noticed. A mw pump with 8mm plungers outputs a heap more fuel compared to the toyota pump.

I have rear somehwere that the rack in the toyota pump is not used to the maximum. Not sire if 5his is correct and why it would be set like this. I may remove the governor cover and have a look to see if anything restricts the rack from moviny all the way.

 

[Nz Nath]

I'll summarise what I know, not just incase it helps you, but also in the hope that somebody who knows more might chime in. I've spent many hours reading up on inline injection pumps on the web, trying to understand the best/easiest way to get more fueling. But there doesn't seem to be a lot of hard facts and reliable thorough information out there. I've read some misleading stuff on old posts here, and have probably posted some inaccurate stuff myself to be fair.

There are pump shops in Australia that rebuild 2h and 12ht pumps in high performance form. One of them, ADS, states they use bigger elements, another which on Facebook have a page JH Hilux do not say anything about elements but do give output figures, I think I recall 280cc for their 2h 'race' pump. The 2h and 12ht should take the same elements as the 3b/13bt, but I think they rotate the opposite way due to the pump being on the rhs of the engine.

The 2h and 12ht pumps seem almost identical to the b series pumps. The b engine manual shows the pump to be the same on all b models, but the governors differ. The 3b looks to share the same vaccum governor as the 2h. The 13bt and 12ht seem to have a denso version of the rqv-k bosch governor. The aussie race spec 2h/12ht pumps keep their original governors, so presumably there is nothing inherently restrictive in either of them.

Not sure what else might be different between the different Toyota pumps, but definitely element size and obviously number of cylinders and governors.

There is some good info from the isuzu 4bd1t guys, mainly on 4btswaps forum. Their pumps are diesel kiki versions of the A pump. A member there had his pump adjusted and bench tested at 180cc by an injection shop. Their pumps have 9.5mm elements. That guy, bush65, wrote a fair bit about these pumps and looked to be trying to find the same info as us about increasing output. Dougal has written that he moved off grid and no longer posts on any forums.

The American shops seem to be able to put 10mm and 13mm elements into A pumps. I've also read that 11mm elements came in A pumps fitted to john deere and case engines used in tractors and excavators. I've read that 10mm elements can be made to put out over 300ccs, and 13mm over 850cc. That seems right based upon what people are getting out of M/MW pumps, but obviously doesn't seem to make sense based on what the Toyota and isuzu pumps put out.


Besides element size, it seems the other variables that effect output are delivery valves, injectors, pump cam lift/duration, rack travel, and how the elements are synced/adjusted to the rack.

If your governor is adjusted to allow full rack travel, you're probably still only getting 18mm of rack out of 21mm (same as all bosch inline pumps by the sounds of it). The rack cover on the front of the pump prevents the final 3mm of movement on the 13bt pump, I suspect it's the same on all Toyota pumps. See the photos below, I cut the end off the cover and welded a bit of tube in between (ugly! It was thin walled galve tube in my defense). I could definitely notice an increase in torque, and smoke at low boost after refitting, so I can conclude my governor is allowing more than 18mm of travel. I would still like more fueling than this though.

In the b engine manual, the total injection volume figures for the 13bt vary between the manual and automatic versions. At intended full rack travel the difference is small, but at 16mm of rack the difference becomes quite sizeable. Maybe there are differences between the pumps, but my suspicion is that the elements are synched to the rack in a more advanced position. I have a scrap pump I bought for $25 just a week or so a go. My next move will be to see if there's any useful rotation of the elements left beyond full rack travel.


I had my injectors rebuilt last year, and lost quite a bit of torque noticeable below 2000rpm. I probably should have looked into this more and asked for my old nozzles. I since read that it's normal to lose power when getting nozzles replaced, as the old worn ones would flow more fuel. One of those Aussie injection shops has posted dynos of a 12ht before and after fitting "+30" nozzles, with no other mods, and there was quite a difference in torque. I'm trying to find more info about injectors, as this seems like a better option of getting more fuel than sending my pump off to aussie. The 13bt nozzles are DLLA150P10. I'd like to find out if I can just fit any other appropriately larger nozzles that are also DLLA150Pxx. I found a pdf catalogue by an Italian company Seven, that lists specs for nozzles. The 13bt nozzles aren't listed, but some other known engines are. I couldn't find any other info on making sense of nozzle codes. I'm curious in what difference the number of holes makes; The b engine manual states the 11b uses 5 hole nozzles, and 13b and 13bt use 4 hole. If smaller holes create better atomization of the fuel, then why doesn't the 13bt run 5 smaller holes? Can anybody who knows about injectors help out here?

Cheers
Nathan

 

[bj70cruzer]

Interesting stuff.

This confirms what i had thought abour rack travel. But seems it still dosnt make much difference. I will take my pump of and measure hownmuch further incan get the rack.

I wouldnt think the indexing of the barrel is the problem but maybe the way the slot is cut into the body (position and depth)?

2nd thought would also be the cam profile.

 

[bj70cruzer]

I had a look at my pump numbers an it seems i have 7mm plungers.
It to it 3mm short on the rack movement so i will turn up a new cap a few mill deper and see how it goes.

Im realy suprised 9mm isnt enough on your 13b, whilst il say i need more fuel im suprised i got this much from my 7mm pump. I thunk a 13b pump would be perfect on my engine .

Too bad its not easier to find in australia for cheap.

I run 20psi boost and it goes quite well but i have room for more fueling

On the steepest hill i would belucky to hit 550degrees celcius pre turbo

 

[Nz Nath]

I'm also surprised that 9mm isn't enough for the 13bt. Here's some more musings, that may or may not be helpful for your 3b pump. I'm really hoping another pump experimenter can add to to this thread.

There's one or two old threads about feed pressure on the 12ht pump. I read these a while ago and the info was floating about in the back of my head half forgotten. The pump pressure is controlled by the overflow valve in the banjo bolt on the return line. There are shims fitted behind the spring to adjust the pressure at which the valve opens. Shims aren't shown in this photo, as I fitted the ones from this spare valve onto my valve to increase the pressure.

There's a guy in the states who makes a heavier duty spring for the mercedes M pumps, and people report noticeable improvement in throttle response and power. The theory is your elements will fill better with higher feed pressure. I stretched my spring a bit, and added the 3 shims from this spare one in addition to the 2 shims that were in mine. Testing with a cheap bicycle pump, the valve opens at 28psi, up from 20psi.

This seemed to make a small improvement at lower revs. The mercedes guys reckon they notice this most at higher revs, I didn't but this could be because my 13bt governor is limiting rack travel way too soon (see below). Also, the mercedes guys are going from 1-1.5bar up to 30psi, so a bigger increase. This may be a good mod on the 3b, as where the manual mentions feed pressures, they are much lower for the b and 3b than 13bt. Whether the lift pump is capable of supplying higher pressure is a different issue, but you could always fit a 13bt lift pump, or maybe rebuild yours with 13bt parts if it can't. The other problem might be not having a tank return line, if you run higher feed pressure it might cause your pump to run too hot.

I've had this scrap pump lying around the living room for a while now without doing anything with it. To get the plungers out the cam needs removing, and to do that you need something to hold the tappets up. Laziness has prevented me from finding something to accomplish this. It's not possible to see how much plunger rotation is available without removing them. When the clamp is loosened to adjust how they're synched to the rack, they seem to be able to spin 360deg.

I think I'm mistaken in believing my governor is allowing full rack travel. It probably is at low revs (I noticed the difference with the longer rack cap), and definitely is with the motor off. The governor's intended working range is barely more than half max rack travel. It seems like the flyweights only create 5mm of travel on the shaft that alters the fulcrum point of the control lever. The movement of that shaft might not be linear with rpm, but it is fixed to it. If the flyweights are able to pull back the rack at 3400rpm at standard rack travel, then they must be pulling it far sooner at nearly double the stock travel. Even with a spare pump to experiment on it doesn't seem possible to observe how this might play out. I think I need to experiment with increasing the preload on the flyweight springs. This will obviously also change both idle behaviour and max speed, but hopefully idle will be manageable with just the control lever stop, and over revving the engine shouldn't be a worry on the road. Maybe more of a concern off road when spinning the tyres up in mud.

I'd be interested to hear if anyone has ever played about with governor springs. And relating to the 3b, it may be that the 3b/2h governor is superior in allowing the use of more rack travel at higher rpms. JH Hilux has commented on one of his facebook posts that their 2h race pumps are capable of more fuel than their 12ht equivalents. I'm struggling to see what the difference could be other than governors. And this is probably the reason that the 9mm elements on the 13bt pump "aren't enough". I wonder whether the governors are interchangeable, and possibly other bosch governors too

 

[bj70cruzer]

Hi nz nath

Your findings are preety much what i have come across aswell.

Interesting with the fuel pressure information as i have watched a few videos on the mercedes pumps a guy known as dieselmeken who makes plungers for the pumps and he talks about how his plungers need 3bar to have full flow (8mm plungers) and how a competitors same size only needs 1 bar.

So i had not figured out how to increase the pressure but from what you have posted inthink thats the way to do it, may need a heavier springs or shims, defitanitly will be experimenting with this.

I only just recently installed a inline low pressure carby type fuel pump feeding to the pump, did not notice any improvements but increasing pressure may make it usefull.
I i lt would of been better if the pump had a return though.

In terms on the governor i think that starts to cut back the fueling quite early but thats one thing im not sure i want to mess with just yet. As it would be fine on the road but 4wding in mud and spinning the wheels could get dangerous.


One thing i realy want to try is modifying the delivery valves. I have not removed mine yet to see whatbit looksnlike but if its anything like a p pump with a outer "ring" on it i want to machine the rings thickness as p pumps seem to gain a decent amount of fueling from using delivery valves with a thinner ring

This is unknown for our pumps and i may end up with scrap delivery valves but im thinking it maybe worth a try?

 

[Nz Nath]

This is a delivery valve out this 13bt pump. It seems to have the ring that you describe... I tried googling the number on it but didn't come up with much. Need to do some more reading about these. I don't think you could machine out the ring by a conventional cutting process? The manual says not to even touch the sliding surfaces of the delivery valves by hand. Could be a specialist job only done by the US tractor pulling guys?

3b could be different due to being idi.

 

[bj70cruzer]

There are a few guys that reckon you can turn it on the lathe.

Not sure how hard the surface is but maybe possible with carbide tips.

Might take one of mine out tonight and measure the band thickness wpuld be interesring to see the difference with a 13bt pump

 

[Nz Nath]

I never got around to posting this, but here is a 13bt 9mm plunger. This would explain why 9mm elements "aren't enough" on the 13bt, the helix isn't very deep (effective stroke length), and terminates in a fuel cut. Hence the annoying reduction in acceleration at full throttle once you've maxed out the fuel.

I've got some Chinese 10mm elements that fit the denso A pump, and I've found an injection shop who's keen to work on it. Originally I got the Chinese elements to confirm compatibility and then get genuine denso items, but I've been told I'd be looking at over 200nzd each and the injection shop are keen to try the Chinese elements.

I'm a little worried the large plungers will result in an overly sensitive throttle and poor idle, but I guess there's only one way to find out.

 

[paul r]

There is great information here. I am getting my 3B pump rebuilt right now. I am adding a turbo and while I definitely don't want to push the limits, I want to make sure I set it up to increase the fuel a bit while being rebuilt. Should I consider using the 9mm elements from the 13BT pump or stick with the 7mm that are in it now? How much should I plan on having them increase the fueling ~25% more? Anything specifically I should seek during the rebuild?

The injection shop also mentioned that they have seen challenges in the past in adding a turbo to the pneumatic governed engines. It seems that there are a lot of 3Bs running with turbos and I would guess the majority still have the butterfly valve and the pneumatic governor so I'm guessing this is not a huge issue or worth changing?

 

[Nz Nath]

Hi Paul,
As you know there isn't a lot of info available for our pumps. I haven't seen anyone post dyno figures for a turbo 3b, or actual bench test figures for any Toyota inline pump. The amount of fueling from a given element is heavily determined by the helix. A 7mm plunger with a deeper helix might provide the same fueling or possibly even more than the 9mm plungers in the 13bt pump. If your shop is replacing the elements anyway (due to wear), then you might consider it sensible to go for the 13bt elements. A larger diameter plunger would inject a given amount of fuel in a shorter time. You'd imagine the cost of the 2 elements to be the same, though it might take more time to correctly adjust the fueling with none stock items.

The diesel shop I've given my pump to have put it on the testbench, they got 104cc /1000shots at 1700 pump rpm. From reading old posts about injection volume, that would be enough fuel for about 450nm at the crank on 4cyl diesel.

 

[Nz Nath]

An update on this. The injection shop had my pump for 5 weeks, which I was a little disappointed by, but I have it back now. There were two issues they encountered with the 10mm elements. I hadn't realized that the top of the control sleeve sits and rotates on the bottom of the barrel. The 10mm barrels were 1mm bigger outside diameter here, so they machined down the outside of the barrels to fit. The 2nd issue doesn't really make sense to me, but on assembly they found the plungers couldn't be passed through the control sleeve, so they had the control sleeves machined somehow. When checking fitment prior to that they and I were apparently inserting the plunger from the other direction.

I was also disappointed by the lack of info they gave me from having benched the pump. The workshop manager believed the 124cc output they'd got was the maximum possible, but when I asked a few technical questions he got the tech out that had built it, who revealed he'd set max fueling to that because he was under the impression I just wanted the pump built to approx 25% more output than before. He told me the elements were capable of outputting over 200cc, which he'd seen when starting to calibrate it on the bench. He couldn't tell me what rack travel it was using, and suggested the fuel could be turned up to about 150cc but would need to go back to the shop for more.

Well the first thing I did when I got the pump home was pull off a few covers and suss out what rack travel it's using. Off boost is about 12mm, and on boost is about 15mm. There is enough movement in the boost compensator/full load stopper to get another 2.5-3mm of rack travel. To get more I'd need to cut the torque cam/plate.

Well I've only done couple of short drives, but I'm really happy with the new performance. There's a very slight 'lopeyness' to the idle, mainly when cold, but otherwise the pump behaves the same as before in terms of idle. I think the boost compensator was set as per book spec to be fully 'on' by 5psi of boost... so hard overfueling, with the smoke clearing up at about 15psi. I added probably a full turn of preload on the star wheel, which helped a bit, but I need to add more as I'm still rolling coal if I give it some jandle at low revs. The performance is great, in 4th gear pulls hard from 60kmh up to motorway speed. Though I probably need to upgrade my clutch, as I had the clutch start slipping a few times accelerating in 4th on hills. I'll try and get a video. I'm definitely now out grunting my common rail triton despite running on heavy 34" super swampers. Cruising egt is either unchanged or possibly marginally better. Egt rises quickly to about 580c pre turbo when booting it, but looks like it would only rise slowly above that on big hills, need to find a steeper hill to test this out on.

I will play a bit more with the boost compensator to reduce the smoke, but otherwise I won't play with the fueling until I switch to a twin scroll turbo setup. I suspect I'll gain headroom for more fuel without having to run higher boost.