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Topic: Gen set thumping? (Read 763 times) previous topic - next topic

Gen set thumping?

Recently, after having steering box replaced, we are experiencing a decided thre bumps when it kicks in.  It did not do this before the replacement.  I have started it from the outside box and it does not appear to be from the engine nor does the tray move.  The front mounts appear to be good.  My friends Onan makes these at kick point but not near as loud.  Ideas?
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: Gen set thumping?

Reply #1 –
George,

Do you have the Isuzu 3LD1 power unit on your generator?
Did they roll the generator out to replace the steering gear?

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Gen set thumping?

Reply #2 –
Tighten the bolts thet hold the genset tray very tightly.  All thumping goes away.  The tech likely pulled the genset out to do the work.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Gen set thumping?

Reply #3 –
Yes that is the gen set and I will retighten the bolts...thanks.  I did not see movement on starting but I did not retighten either.
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: Gen set thumping?

Reply #4 –
If tightening the tray bolts does not fix the thump, check the four rubber mounts which are between the generator frame and the drawer slide. Mine were disintegrated and causing metal/metal contact.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: Gen set thumping?

Reply #5 –
Thanks all...it appears the tightening worked but there is significant deterioration of the back mount and some contact can be heard.  The thump was from the rear and I couldn't see movement of the tray. 
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: Gen set thumping?

Reply #7 –
Thanks for the link!
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: Gen set thumping?

Reply #9 –
Thanks Mark...when you separated your gen set what was the gap measurement you used?
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: Gen set thumping?

Reply #10 –
Quote from: George and Steph –
Thanks Mark...when you separated your gen set what was the gap measurement you used?

I mounted the lower frame under the radiator to the deck with additional mounts like the engine rests on. Only after that did I cut the frame connecting the radiator to the engine. That allowed all the spacing to stay the same as original.

Mark
The selected media item is not currently available.
Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara

Re: Gen set thumping?

Reply #11 –
I apologize for how I worded that Mark.  How much needs to be cut away so the two ends don't come into contact? 

George
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: Gen set thumping?

Reply #12 –
Quote from: George and Steph –
I apologize for how I worded that Mark.  How much needs to be cut away so the two ends don't come into contact? 

George
Sorry. I just cut maybe 1/4 inch out or so. I could measure if you want.

Mark
The selected media item is not currently available.
Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara
 

Re: Gen set thumping?

Reply #13 –
Went out and looked and 1/4 to 3/8 looks good.  Thanks for getting back to me.  Located a lift and having at it next week.  The mounts, tape, insulation, etc have all come in now.  Your documenting of the process is so helpful.  Been referring to it as the MAZ method.
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P