MEP-003 bolt torque spec

[Crawdaddy]

Hopefully sometime this week I will be installing my newly purchased injector and injector pump on my MEP-003. I've looked in the TMs for what the torque of the bolts should be that hold the injector to the head with no luck. It just says to "install" the injector. What should I be torquing the bolts to?

 

[NJ_Toolnut]

Hi Crawdaddy,

Table 1-1 in Chapter 1 of TM-34 is the table that contains torque specifications. It states the torque spec for the injector nozzle mounting screws is 17-18 ft/lb. I was not able to find the torque spec for the nuts that hold the IP to the threaded studs on the cylinder block in TM-34, but according to my copy of the Onan manual for the DJE engine, the torque spec for these nuts is 15-16 ft/lb. Due to their tight location, I did not even try to use a torque wrench on these nuts when I reinstalled my IP. It was difficult enough just to get an open-end wrench on them. I just tightened them an "across the corners" sequence 180 degrees apart, going around three times until I considered them tight enough. You can probably obtain 15-16 ft/lb fairly easily using an open-end wrench one-handed.

Best regards,

Stan

 

[Crawdaddy]

Thanks for the help Stan. I didn't notice, nor think about the table in the begginning. I guess I'm just used to the TMs putting the torque specs inline with the instructions throughout the TM.

To be honest, 17-18 foot pounds seems a little low for something that needs to be held in and seal against massive burns of fuel creating thousands of psi of pressure. But, if that's what the spec says, I'll do it.

 

[Bill W]

Thanks for the help Stan. I didn't notice, nor think about the table in the begginning. I guess I'm just used to the TMs putting the torque specs inline with the instructions throughout the TM.

To be honest, 17-18 foot pounds seems a little low for something that needs to be held in and seal against massive burns of fuel creating thousands of psi of pressure. But, if that's what the spec says, I'll do it.

17-18ftlbs is correct
I changed out injectors on my first mep-003a and back then ( before I got manuals ) the injector guy told me that the standard is usually about 15-18ft/lbs for all injectors in general, of course I did not believe him and started to put them on tighter towhich I noticed the injector bracket starting to bend.
The torque for the injectors on the deuce are 12-15ft/lbs ( though I think it was raised to 17ft/lbs )

 

[Carl_in_NH]

The Onan / AMBAC specs are indeed correct. The nuts on the pump studs can be done with a torque wrench, you just need to use the proper sized crow's foot that's been kicking around in the bottom of your toolbox for the last couple decades to get in there. This setup worked well for me.

 

[NJ_Toolnut]

+1 on crow's foot. If I'd had one kicking around in the bottom of my toolbox, I would have tried it. I think when using a crow's foot, actual applied torque will differ from torque wrench setting, so calculation/adjustment to wrench setting to compensate will be required.