no injection/pulsation on cylinder no. 5

[Casar66]

This weekend the engine did not run smooth like usually. On the line of cylinder 5 I missed the pulsation. The injector produced no gas even when I pulled the needle at the top, only drops, time by time. So I changed the injector. No difference. I changed the banjo-valve. It runs nice like before (only a short test in the garage). But this morning the same, no pressure/no pulsation on line 5. All others are fine. What could it be?  

[Casar66]

Just checked the line. no leaks. But there is no petrol in the line. I separated the line from injector and startet the engine. No petrol came out. After a while few drops. Thats all.

[TR6_PI_1969]

Hi, could this be of any help? 

[Casar66]

I don't know. The pipes are not leaking. There is no fault in the connection to identify. I have always thought that problems with just one cylinder is always a fault on the injector, the pipe or the (banjo-)valve. Valve is new, injector is new, the pipe seems ok, no leaking, no damages.

[Casar66]

Just have checked the pipe and the connections, no leak (with air under water) it is definitely sealed.

[astontr6]

43 minutes ago, Casar66 said:

Just have checked the pipe and the connections, no leak (with air under water) it is definitely sealed.

I believe that you have an air lock? When you primed that fuel line did you back fill that injector line with petrol until full before screwing on the injector? That method s/b used when ever you work on the M/U and its N/R valves. I am assuming that your fuel pressure to M/U is correct?

Bruce.

[Yarm 783]

With the engine running if you pinch the pipe between thumb and finger it should pulse, if not then bleed the injector to get the air out until you see fuel.  There are plenty of posts and advice on the best way to do this, I have used a glass jar and some needle pliers, but I have seen others simply flicking the injector against something solid.

[Casar66]

I did already that, please have a look at the 1. post. 

Tonight I did exactly the same, only difference : I filled the pipe with petrol before connecting the injector (what Bruce has recommended). Again, it ran nice. I did a 10min drive, everything was good. But yesterday it ran also nice but this morning cylinder no. 5 has failed. Hopefully there is no deja vu tomorrow morning.

[Mike C]

Before I had my PI system rebuilt   I used to have all kinds of airlock problems with no 2 and no 5 injectors, especially no 5. I suspect that the NRV's on the MU banjo connectors were leaking, allowing  the injector lines  to drain down when the engine was shut down for a while.

[matttnz]

Might be worth checking the plug on cyl 5 as well?

[Casar66]

back from my morning-run. Everything seems ok. 

[astontr6]

1 hour ago, Casar66 said:

back from my morning-run. Everything seems ok. 

Hi Casar 66!

I am glade that you are making progress! Are you still using the CAV filter system? as these can collect air in them and if the bleed screw is not undone every 12months can send a big air lock to the injectors and stop 2 & 5 working properly and others. This has happened to me in the past! Petrol can contain a lot of dissolved air in it.

Bruce.

[Casar66]

I am using a Bosch pump since 16 years without any problems. Everything else is standard, the tank, the drain, the PVR. Sometimes the MU made some problems ( like the current one, one, both diaphragm damaged, injectors need new seals). But the system runs very stable and reliable. And you can fix it one the run. I like it a lot. 

[c.hydes]

35 minutes ago, astontr6 said:

Hi Casar 66!

I am glade that you are making progress! Are you still using the CAV filter system? as these can collect air in them and if the bleed screw is not undone every 12months can send a big air lock to the injectors and stop 2 & 5 working properly and others. This has happened to me in the past! Petrol can contain a lot of dissolved air in it.

Bruce.

Hi Bruce, didn't know I had an air bleed screw let alone venting it every two years. Can you share where it is, looks like, photo etc?

Cheers, Colin. 

[astontr6]

7 minutes ago, c.hydes said:

Hi Bruce, didn't know I had an air bleed screw let alone venting it every two years. Can you share where it is, looks like, photo etc?

Cheers, Colin. 

Hi Colin,

I have not used the CAV filter system for years! The bleed set screw is on the top of the filter canister off set to one the side. A 7/16" UNF spanner fits. Please note: I am going from memory! It is not the Centre set screw which holds the unit together.

Bruce.

[c.hydes]

38 minutes ago, astontr6 said:

Hi Colin,

I have not used the CAV filter system for years! The bleed set screw is on the top of the filter canister off set to one the side. A 7/16" UNF spanner fits. Please note: I am going from memory! It is not the Centre set screw which holds the unit together.

Bruce.

Thanks Bruce i`ll go have a look.

Colin.

[kcsun]

Do you have a separate filter for the Bosch pump, have you replaced that filter recently, I change mine at least twice a year (only £1.50 - £2 each) they always have loads of crud in them from my petrol tank

kc

[astontr6]

3 hours ago, Casar66 said:

I am using a Bosch pump since 16 years without any problems. Everything else is standard, the tank, the drain, the PVR. Sometimes the MU made some problems ( like the current one, one, both diaphragm damaged, injectors need new seals). But the system runs very stable and reliable. And you can fix it one the run. I like it a lot. 

I am taking about the original CAV filter system that some people use in conjunction with a Bosch Pump, in my view not recommended, unless pipe mods have been done as well. Bosch pumps do not like the 1/4" bore pipework as it does not give enough free flow to the pump but this was also a problem with the Lucas pump which BL never rectified.

Bruce,

[Casar66]

I think that the problems with the Bosch is the pressure and the delivery capacity they work with. It is very importantant to choose the right one. Most of the Bosch equipped TRs have too strong pumps and due that they need the bigger drain, tuned pvr- valves and still have problems with the heated petrol. Just my thoughts.

Edited August 4, 2020 by Casar66

[Waldi]

5 hours ago, Casar66 said:

I think that the problems with the Bosch is the pressure and the delivery capacity they work with. It is very importantant to choose the right one. Most of the Bosch equipped TRs have too strong pumps and due that they need the bigger drain, tuned pvr- valves and still have problems with the heated petrol. Just my thoughts.

Hi Casar,

Which Bosch type do you have and how much current does it draw?
Thanks,

Waldi

[Casar66]

it is the Bosch 996. Unfortunately it is out of Boschs portfolio since the early 1990s. Sometimes you will find one on Ebay but they are very expensive (around 300-500 euros, dollars or pounds).

But I have found a very cheap substitute from Poland (the make is ESEN) for around 40 euros in good quality. I have not try it yet due different hose connection but the data seems to be very promising. 

 

 

Edited August 5, 2020 by Casar66

[Waldi]

Aha,

Thanks, I will have a look if I can compare pump curve data.

Cheers,

Waldi

[Casar66]

I don't think that you will find the needed data online.  The Bosch 996 makes up to 90l/hour, 750 ccm within 30 seconds at 5 bar pressure. The Esen is the same but at 4bar. So  guess there will be also none of the well known problems when switching to Bosch with too high capacity. The only risk I see is that the Esen produces at just 4bar. Maybe that could be a little low. But on the other hand - if 4 bar is enough - it could be even better than the Bosch. 

[Mike C]

4 bar is not enough, but maybe you're looking at the wrong point on the pump curve. To match the  Lucas original pump you need something like 7 bar at 72 litres/hour.

[Casar66]

the Bosch produces - according to the data sheet - just 5 bar and runs perfect.