Glow plug health, how to tell?

[TMB1320]

So I’ve decided to at least service the glow plugs, take them out and decarbonise, bores also.
There is another thread here on TBN (didn’t bookmark, darnit) that had similar starting issue on a NH 1710 I believe it was. He noticed that the center glow plug was sooty when removed. He didn’t mention that he reamed the bores, and probably didn’t. After replacing GPs, and starting, it made a knocking noise and
reported on the thread. After a few back and forth on the thread on what it might be, it went quiet.
I suspect that a chunk of carbon got pushed into the combustion chamber, and eventually disintegrated or exited through the exhaust. I hope to avoid such problems by careful cleaning of the bore and borescope inspection. I would like to replace the original GPs with a Bosch product, but after searching have failed to
find a Bosch part number for the SBA185366190
Anyone here have a Bosch part number? A link to a source would be greatly appreciated.

 

[TMB1320]

Where are all the TBN tractor glow plug aficionados?
The silence is deafening.

 

[kirkawilson]

Might be able to match the glow plug dimensions from the table starting on page C1. View attachment Bosch_Glow_Plug_Web_Ready.pdf

 

[RickB]

I was thinking a tip might be to open the air bleed on top of injector pump BEFORE removing filter bowl to avoid pulling fuel out (air in) the inj pump. Just a guess. Thanks for the reply.

That works exactly opposite of what you think. You instantly drain the line from filter to IP.

 

[RickB]

So I’ve decided to at least service the glow plugs, take them out and decarbonise, bores also.
There is another thread here on TBN (didn’t bookmark, darnit) that had similar starting issue on a NH 1710 I believe it was. He noticed that the center glow plug was sooty when removed. He didn’t mention that he reamed the bores, and probably didn’t. After replacing GPs, and starting, it made a knocking noise and
reported on the thread. After a few back and forth on the thread on what it might be, it went quiet.
I suspect that a chunk of carbon got pushed into the combustion chamber, and eventually disintegrated or exited through the exhaust. I hope to avoid such problems by careful cleaning of the bore and borescope inspection. I would like to replace the original GPs with a Bosch product, but after searching have failed to
find a Bosch part number for the SBA185366190
Anyone here have a Bosch part number? A link to a source would be greatly appreciated.

You break the carbon loose with a reamer where do you suppose it ends up?

 

[TMB1320]

Thanks Kirk that’s a wonder Bosch catalog. I will be referencing it when I get one/all out.
Too bad there isn’t a catalog for tractor cylinder heads.

 

[TMB1320]

That works exactly opposite of what you think. You instantly drain the line from filter to IP.

Totally expected, as long as it doesn稚 take any fuel out of injector pump. My thinking that refilling the filter bowl
and the 1/8 x 10 line from the filter to pump will purge the air after the shutoff valve is opened. Once it痴 full,
and flowing, close the bleeder on top of the inj pump.

 

[TMB1320]

You break the carbon loose with a reamer where do you suppose it ends up?

According to the instructions, it’s supposed to stick to the non silicon grease applied in the flutes prior to use. My fear would be that a chuck the size of the bore gets pushed in instead of chipping out.

 

[thepumpguysc]

Your WAY over thinking this process..
Take out the GP's> run a reamed if you have one, if not, don't worry about it.. Spin the engine over a sec or 2 to blow the carbon out & reinstall the GP's.. Takes less than 20 minutes for goodness sake..
IF you have a reamer. dip the flutes in a jar of vasoline.. the chips or "whatever" will stick to the reamer.. then spin the engine over w/o the GP,s in to blow out any residuals.. The heat from the running engine will take care of the rest..

 

[TMB1320]

Your WAY over thinking this process..
Take out the GP's> run a reamed if you have one, if not, don't worry about it.. Spin the engine over a sec or 2 to blow the carbon out & reinstall the GP's.. Takes less than 20 minutes for goodness sake..
IF you have a reamer. dip the flutes in a jar of vasoline.. the chips or "whatever" will stick to the reamer.. then spin the engine over w/o the GP,s in to blow out any residuals.. The heat from the running engine will take care of the rest..

I don’t think they have ever been removed. At least 20 years, and 3750 hrs. So I’m not going to attempt
it until the snow is gone, just in case things go pear shaped like Ive seen in some of the DIY vids.