Bongo Fury

Thanks to Ron Miel (David's) nagging , I am finally getting round to writing to all garages on the database, asking them if a) their current entry is correct, b) they are willing to service petrol Bongos; and c) if they want a copy of the workshop manual. This will be done this week.

Ian wrote:Thanks to Ron Miel (David's) nagging , I am finally getting round to writing to all garages on the database, asking them if a) their current entry is correct, b) they are willing to service petrol Bongos; and c) if they want a copy of the workshop manual. This will be done this week.

Thanks Ian. An extra field in the Bongo-friendlies database to tell us which garages have the manuals (all varieties) would be useful to us, and might help motivate more of them to purchase. Realise the update problem, though. Failing that, a strong warning on the database, to encourage peeps to ask the question before placing work with garages, might be just as effective.

Hi Jamie,

Check that link out I posted, it tells you there. I know my V6 has timing marks on the lower half of the engine from the recent work, that link tells you where to connect a strobe and how many degrees it should be set at at a certain RPM, from memory it was 12 degrees at 700RPM.

Download it and give it a read, just takes some time but no cost.

If you don't want to do it you can print it off and give it to a garage?

Andy

apole wrote:Hi Jamie,

Check that link out I posted, it tells you there. I know my V6 has timing marks on the lower half of the engine from the recent work, that link tells you where to connect a strobe and how many degrees it should be set at at a certain RPM, from memory it was 12 degrees at 700RPM.

Download it and give it a read, just takes some time but no cost.

If you don't want to do it you can print it off and give it to a garage?

Andy

Hi Andy
I don't have the unpacking software to read those .rar archived files, so have not looked at the 929 engine adjustments section you've given the link for, but does it also include the related stuff on offload/onload idling checks/adjustments and emissions checks, as in the translated Bongo V6 engine workshop manual? I think you can infer from the latter that, although you can set up your ignition timing by distributor adjustment, using just a strobe, in doing so you may adversely alter any or all of those other facets.

Hi Jamie
If you are going to tackle just standalone offload* ignition timing, without measured reference to the other facets, and in case the V6 Bongo data from the workshop manual, differs from the Mazda 929 engine data in any way, it is:

- warmed up engine.

- shift lever in P position

- idler revs within 500-900 rpm (it says to check by using an external calibrated tachometer connected to the diagnosis connector IG negative terminal - not by using the instrument panel rev counter).

- adjust idle speed if necessary to achieve that, by turning the air adjusting screw.

- yellow crankshaft pulley alignment marks, within BTDC 12 +/- 1 degree, with TEN terminal shorted to GND terminal.

- rotate distributor if necessary to achieve that, then tighten to a torque of 19-25Nm (1.9-2.6kgf/m)

- re-check that the idle speed is within 500-900 rpm, and re-set if necessary (and, presumably, then re-check ignition timing)

- remove the TEN to GND short circuit

- check that the yellow crankshaft pulley alignment marks are within ATDC 6 degrees and BTDC 23 degrees

After that, the Bongo V6 engine's workshop manual process continues with more precise idling adjustment offload, to a standard value of 700 +/- 20 rpm, followed by a range of onload "idle up" tests, idling emission tests, then finally emissions reduction during deceleration tests - at all stages cross checking with the ignition timing (and other system elements) before and after any adjustment, and using all the test and measurement devices I previously listed.

*("offload" in the above, means all of the following switched off: all electronics except engine management; headlights; blower motor; rear defroster; power steering.)

Hope that helps, and good luck.

Ron Miel wrote:

apole wrote:Hi Jamie,

Check that link out I posted, it tells you there. I know my V6 has timing marks on the lower half of the engine from the recent work, that link tells you where to connect a strobe and how many degrees it should be set at at a certain RPM, from memory it was 12 degrees at 700RPM.

Download it and give it a read, just takes some time but no cost.

If you don't want to do it you can print it off and give it to a garage?

Andy

- rotate distributor if necessary to achieve that, then tighten to a torque of 19-25Nm (1.9-2.6kgf/m)

- re-check that the idle speed is within 500-900 rpm, and re-set if necessary (and, presumably, then re-check ignition timing)

- remove the TEN to GND short circuit

- check that the yellow crankshaft pulley alignment marks are within ATDC 6 degrees and BTDC 23 degrees

Hope that helps, and good luck.

I don't understand that bit - thats a helluva tolerance................

dandywarhol wrote:

Ron Miel wrote:

apole wrote:Hi Jamie,

Check that link out I posted, it tells you there. I know my V6 has timing marks on the lower half of the engine from the recent work, that link tells you where to connect a strobe and how many degrees it should be set at at a certain RPM, from memory it was 12 degrees at 700RPM.

Download it and give it a read, just takes some time but no cost.

If you don't want to do it you can print it off and give it to a garage?

Andy

- rotate distributor if necessary to achieve that, then tighten to a torque of 19-25Nm (1.9-2.6kgf/m)

- re-check that the idle speed is within 500-900 rpm, and re-set if necessary (and, presumably, then re-check ignition timing)

- remove the TEN to GND short circuit

- check that the yellow crankshaft pulley alignment marks are within ATDC 6 degrees and BTDC 23 degrees

Hope that helps, and good luck.

I don't understand that bit - thats a helluva tolerance................

Neither did I - hoped you, or somebody else, might I've paraphrased all of the above, for brevity, but that's what it says - following removal of the jumper, so does it whack about wildly for some strange reason, once that's removed? Otherwise, translation error and/or typos? There's bound to be a few, although if so that would be a disappointingly gross one Ian?

If its anything like the Kiwi translated diesel manual then it's full of mistakes

dandywarhol wrote:If its anything like the Kiwi translated diesel manual then it's full of mistakes

Hmmm! Bearing in mind the relatively high cost of these manuals, do you know if any effort has previously been made to get apparent errors re-checked, and errata published when necessary?

To complicate matters further: apole has forwarded a copy to me of the "Adjustments" section from the 929 (and other Mazda engines) data, he gave a link to earlier. It is from a publication by Techdoc, independently produced in 1997 by Mitchell International, apparently for the US market, and so is not an original Mazda source.

Anyway, it covers ignition checks/adjustment (as above) and TPS checks/adjustment, but instead of the idling and emissions checks/adjustments in the translated Bongo V6 engine workshop manual, it just says:

"IDLE SPEED & MIXTURE
NOTE: Mixture adjustment is NOT a normal tune-up procedure. DO NOT
adjust mixture unless mixture control unit is replaced or
vehicle fails emissions test."

......so that's apparently the American approach to it all!! You pays your money, and you takes your choice but there's still mpg, components longevity, emissions and the MOT to consider.

Surely, in any case, and as properly taken account of by the workshop manual, ignition adjustment itself affects mixture and emissions control, so they should be adjusted iteratively - and to not do so is asking for trouble(?). Idle speed/mixture adjustment in the workshop manual process is by simply turning the air adjustment screw BTW, so not rocket science in itself - but it's the offload/onload idling measurement, and resulting emissions checks that require some kit.

From "Hillier's Fundamentals of Vehicle Technology", Book 1, Page 189, Introduction to Engine Management Systems:

"The ignition and fuel control systems have been integrated into one computer (ECU) referred to as an engine management system. The integration of the two systems provides precise control of the ignition timing, which operates in conjunction with the fuel system. Co-operation between the two systems provides the optimum ignition timing together with the correct mixture over the entire operating range of the engine, thus giving the lowest emissions."

(Presumably, dependent on correct distributor alignment at idle, and correct idling speed set up, as the baseline positions from which the ecu computes at other speeds.)

BTW Jamie, not sure whether you got a positive I.D. on the mystery distributor sensor thingey you had to find a replacement for in the thread preceding this one, but the same source (Hillier) spells it out as a "Hall Generator" - a contact-less electronic replacement for the old style cam-driven distributor contact breaker. It works by rotating vanes (one per cylinder) below the rotor arm, sequentially exposing/screening a "Hall effect" integrated circuit from a magnetic field which is created across a small air gap by a fixed magnet. As soon as the IC is exposed to the magnetic field, it signals the ECU to initiate spark generation - so it's the position of the vanes relative to crankshaft position that's altered in ignition timing adjustment. EDIT: Just found the earlier thread and see that mikexgough did I.D. the Hall Effect gizmo - anyway, that's what it does.

found my v6 bongo distributor.

Good to hear this Jaimie.

If its anything like the Kiwi translated diesel manual then it's full of mistakes

Hmmm! Bearing in mind the relatively high cost of these manuals, do you know if any effort has previously been made to get apparent errors re-checked, and errata published when necessary?

I expect Ian will get this clarified, as there is discussion of them being promoted to garages (who don't all have their own sources).

Ron Miel wrote:

dandywarhol wrote:If its anything like the Kiwi translated diesel manual then it's full of mistakes

Hmmm! Bearing in mind the relatively high cost of these manuals, do you know if any effort has previously been made to get apparent errors re-checked, and errata published when necessary?

JPNZ are responsible for the content, not us. They will have translated the settings from the original Japanese Mazda engineer manuals.

All I can suggest is that where known errors have been found these are listed here, and I will then include them in an "erratum" note that I send out with the manuals.

Known errors should be reported in the following format:

Volume 1, page 63, third paragraph. Delete "xxxxxxxxxxxx", replace with "YYYYYYYY".

Ian wrote:

Ron Miel wrote:

dandywarhol wrote:If its anything like the Kiwi translated diesel manual then it's full of mistakes

Hmmm! Bearing in mind the relatively high cost of these manuals, do you know if any effort has previously been made to get apparent errors re-checked, and errata published when necessary?

JPNZ are responsible for the content, not us. They will have translated the settings from the original Japanese Mazda engineer manuals.

All I can suggest is that where known errors have been found these are listed here, and I will then include them in an "erratum" note that I send out with the manuals.

Known errors should be reported in the following format:

Volume 1, page 63, third paragraph. Delete "xxxxxxxxxxxx", replace with "YYYYYYYY".

Problem with that approach Ian, is that in some cases (possibly most cases), including the one above which dandy warhol and I both suspect is very wrong, we've no idea what the correction should be - unless JPNZ look again at their translation. If they benefit from the sales, and want more, they should do that, in their interest and ours. Can we report suspected errors to you, to check with them? If we can, then a "suspected error" reporting slip tucked in the front of each manual sold would do the trick.

Ron Miel wrote: Can we report suspected errors to you, to check with them? If we can, then a "suspected error" reporting slip tucked in the front of each manual sold would do the trick.

Yes, that will be fine.

Ian wrote:

Ron Miel wrote: Can we report suspected errors to you, to check with them? If we can, then a "suspected error" reporting slip tucked in the front of each manual sold would do the trick.

Yes, that will be fine.

Thanks. Will you check on this one, please?

Ron Miel wrote:

dandywarhol wrote:

Ron Miel wrote: >
>
>
- rotate distributor if necessary to achieve that, then tighten to a torque of 19-25Nm (1.9-2.6kgf/m)

- re-check that the idle speed is within 500-900 rpm, and re-set if necessary (and, presumably, then re-check ignition timing)

- remove the TEN to GND short circuit

- check that the yellow crankshaft pulley alignment marks are within ATDC 6 degrees and BTDC 23 degrees
>
>

I don't understand that bit - thats a helluva tolerance................

Neither did I - hoped you, or somebody else, might I've paraphrased all of the above, for brevity, but that's what it says........translation error and/or typos? There's bound to be a few, although if so that would be a disappointingly gross one Ian?