BrewPub

Since this forum is for 4 valve per cylinder, I am posting the Isb 3.9L query here.

Does anyone have experience/knowledge of the vibration issue or non-issue regarding the Isb 3.9 liter 4 cylinder 170 hp engine.
The 4bt is known to have considerable vibration issues. I am not quite sure but from my reading up on cummins 4 cylinder engines, it seems the ISB 3.9L is the successor to the 4bt.

Thanks

jrs_dodge_diesel

Never heard that those engines vibrate more or less than our 6 cylinder. Do you have one that is giving you any trouble?

BrewPub

Don't have an ISB yet but planning on getting a new or near new 1 for a repower.
People talk of the inherent imbalance of 4 cylinders and vibration as a result which is why I ask.The 4bt the predecessor to the 3.9 ISB is well know for vibration.

Where can ISb 3.9 be found (automotive apps)? Does fed-ex.ups use them currently? Would like to take a ride in a vehicle eqipped with the ISb 3.9 to hear/feel for myself the vibration issue or non-issue.

pind

We recently installed a 3.9bt on a floater here, for powering the hydraulic drives associated with the unit. the unit came on its own skid, with an over center clutch and 4 v-belt sheave installed. having run it through its operating range, in order to find the optimum rpm for the pump drives, I have seen no noticeable vibration from the unit.
I have also worked on many 3.9bt and bta units in power generation, where excessive vibration is a death rattle, and have had no problems with them there either.
the 3.9 ISB would be the logical leap from the old one lung b series. Nice to see them properly valved, and I cannot see a reason for excessive vibration in these either. That being said, generally a 4 cylinder diesel will not run as smooth as a 6. That is just a fact. which is why some smaller industrial 4 cylinders have balance shafts, IE 3304 Cat.
Good luck with whatever you choose to do. Also, take the time to look into the perkins 4 cylinder diesels, if it is a repower that you are doing. Excellent units, good power to weight, and excellent fuel consumption / hp numbers.

have fun

BrewPub

Perkins

Are these 4 cylinders still being manufactured and wahts the spare/parts service like in North America. Do they have a proven record for reliability/durability? I know cummins is top notch just wondering how the Perkins stacks up.

Thanks.

pind

wow, more than 1 reply a day, I need a life...

Perkins has been working very well, with both the 4 and 6 cyl. engines. regular service life of 25,000 + hours. The only reason we went with the 4bt on the floater, is it had already been purchased for the project, and shipped over from NZ with the rest of the unit.

I am a perkins dealer on this side of the border, and have yet to run in to any problems with parts availability. I will admit that there are some sticky issues with warranty support, however, if you read the fine print, you will see that most engine manufacturers are the same, in regards to filtration, oils, etc. And most of them will at least try to find fault on the part of the customer if there is a failure.... ( Ever bought a Dodge??? )
I did experience a catastrophic failure on a 1006 series ( 6 cyl.) unit, powering a 105 Kw gen. less than 8 hours on the unit, and it seized a piston in the liner, and created a very expensive pile of art. I got the call from the customer, I called the regional office and emailed some pics, and within 5 hours, we had a complete new (not reman) engine assembly on the way. This included rad, and all peripherals. To me, that is reasonable after-sale service.

Perkins has also been used in farming equipment since dirt was invented. And they seem to hold up quite well in that application. Lots of 4cyl stuff there, mostly old 4.236 engines.

Go with what will work best for your application, and good luck with it.

PM me if you need more info

storx

we have some int he generators on base and they do viberate a lot but the timing seems to make a big difference if you adjust it to what you need power wise.. we turn the timing out about 5/8's of a turn on the pump srew and it smooths it out and then every so often we have to adjust it again it seems to move after a while the sweet spot of these engines...

BrewPub

Do you mean ISB generators? I think Cummins makes a stationary industrial app ISB and Automotive app ISB.

Does adjusting the timing decrease or increase power output (hp & torque)
Is a balancer used?

Thanks