Difference between RA and JR pump???

[Anonymous]

Anyone know what the exact differences are between these 2 pumps? My JR pump started leaking and I had the RA pump lying around so I just swapped them over. I just want to know if the RA deliveres more fuel etc.. all info welcome..

[Caddy-Daddy]

Strange thing I didn't post this as a guest I was logged in...

[fspGTD]

What's a JR engine?  It isn't ringing a bell for me...

[Caddy-Daddy]

JR engine that's the 1.6TD from all mk2 's or A2's in the US, must ring a bell...

[Caddy-Daddy]

No Body ??

What's the engine code than there in the US for the 1.6TD of the A2 Golf?Jetta..?

[type53b_gtd]

A2 turbodiesels were MF code engines - after mid-86 they had hydraulic lifters, before that, they were solid.

The JR is a Europe only version of the 1.6TD  - likely any difference between the MF and the JR is subtle.

The RA was intercooled, so it can be expected that the RA pump will be set up to deliver more fuel.   The RA pump also had different pressure valves on the pump, and also had (likely higher breakpoint) injectors.

To be safe you might want to swap the pressure vlaves from the hydraulic head of the JR pump onto the RA pump, and if you don't like the smoking characteristics after that, adjust the fuel delivery...

Drew

[RedRotors]

The RA pump also had different pressure valves on the pump, and also had (likely higher breakpoint) injectors.

Drew

The RA, SB engine got the same breaking pressure on the injector ( 155bar ) as our MF here..  :wink:

Marc/

[type53b_gtd]

The pressure valves the cut flow to the injectors are a different part number of the RA/SB pump: 068 130 795 B vs 068 130 795 on the rest of the 1.6 TD pumps.  As I understand it these valves close below a set pressure to cut fuel flow to the injectors and prevent dripping and coking.

So the question is, do they cut in sooner or later on the RA?  Are there other internal differences in the RA/SB pump?

One external difference on the RA/SB pump is that the Family Album shows the governor lever damper (as found on the 1.9 AAZ pump) being used.

As an aside. the RA/SB originally listed different nozzles (211 F vs. 211 D) was it ever determined what the difference really was?

[Caddy-Daddy]

Are these pressure valves located inside the Pump? Sorry I'm a newbee conscerning pumps.  Since I swapped to the RA pump I noticed an increase in acceleration. It pulls much stronger. I haven't swapped the injectors yet.. I will soon as I have the proper tool to take them off the RA Head.

 

One external difference on the RA/SB pump is that the Family Album shows the governor lever damper (as found on the 1.9 AAZ pump) being used.

Is this a good or bad thing?

[type53b_gtd]

Are these pressure valves located inside the Pump? Sorry I'm a newbee conscerning pumps.  Since I swapped to the RA pump I noticed an increase in acceleration. It pulls much stronger. I haven't swapped the injectors yet.. I will soon as I have the proper tool to take them off the RA Head.

The valves are threaded into the distributor head at the end of the pump - the hard lines to the injectors then connect to the valves.

Is this a good or bad thing?

Beats me - I have yet to determine what purpose it serves on the AAZ pump.  It appears to only function through the first part of the governor control lever's operation - after about half way the damper is fully compressed.  Perhaps it is there to dampen vibration (seems unlikely) or to dampen the action of the control lever springs.  Anybody else?

[Caddy-Daddy]

I have a blown headgasket now.. I 'm going to swap the complete RA head now.. will do it ,once it's skimmed flat again. Is that the correct word for it? " Skimmed " ? to make it flat I mean.

I already have everything off but the injectors. I noticed small cracks in the swirlchambers starting from the small openings.  Is this normal ?

I know the cracks between the intake en outlet valves is normal. I have a few of those to on the RA head.

I still have the valve seals in.. how can I remove those? And is it wise/better to replace them aswell?

[type53b_gtd]

Because there is so little clearance bwteen the valves and pistons in the 1.6 diesels "skimming" the head is not recommended, especially if too much material needs to be removed.  If you have a one or two hole (or notch) gasket you can gain a wee bit by going to a three notch, which is the thickest gasket, but ithe difference in thickness between the headgaskets is only .04mm.

As far as cracks go, cracks in between valve seats are to be expected, and are acceptable if they're less than .5mm wide per the Bentley (although I have seen wider cracks without issues.)

However, if you have cracks in the combustion chamber inserts, then you'll want to check the head very closely.  Although you can swap out combustion chamber inserts, there's a chance that there may be orther cracks in the head as well.  If the cracks are in the head and near the combustion chamber inserts, then it is junk.  Remove the valves and carefully inspect for cracks, or send it to a machinists to have this done.

As far as valve stem seals go, you should replace them at this point, but more important are the guides - especially the exhaust guides, which wear.  The old guides can be pressed or driven out and new ones pressed or driven in, then you can install new valve stem seals.

Drew

[Caddy-Daddy]

Thanks Drew for your comment.. learn something everytime about my favourite engine.

Just got a phonecall today from the shop, the RA head is cracked.So I have to bring the one on the engine now to the shop.

First have to get it out... Damn!!! Summer just started over here in Holland but the weather thinks otherwise. Its !@#$%^Storming and raining like crazy.. windspeeds of 120Km/h .Since I don't have a garage or anything similar I'll have to wait untill the weather calms down again.

Ronny aka Caddy-Daddy

[Caddy-Daddy]

Finally got the head removed... but sadly it's cracked aswell... and cracks are even worse than my RA head. It even has a large crack from the Valve to the swirlchamber...

Picture's will follow.

Anyway as I was looking for another head, a friend of mine said there were 3 complete JR/MF blocks lying around at the breakers. He is going to pick the best one out for me since it's closer to were he lives.

So this means I'll get a complete engine for just 250 Euro's and it will be delivered at my doorstep.. what more do you want?      

[Giles@PerformanceDiesel]

Hey guys

it's much easier for me to give info when u give me the correct
Bosch 10 digit pump assembly #.

that way i can look it up on my computer and tell anything u want.

Giles