D180 Oil Fill Cap Blew Off

[S416-8 397]

So got a shock today when I went out, started the 180 and after a few min's of warming up the oil fill cap blew off with enought force to never be found again.. I haven't checked the vent house yet and with the -15 winds I get to it later just plug the fill tub and put a small trash can over it.. good thing I hope is before I got to it to shut it down the engine had no strange noises and seem to run ok..   

[lynnmor 8,471]

2 minutes ago, S416-8 said:

So got a shock today when I went out, started the 180 and after a few min's of warming up the oil fill cap blew off with enought force to never be found again.. I haven't checked the vent house yet and with the -15 winds I get to it later just plug the fill tub and put a small trash can over it.. good thing I hope is before I got to it to shut it down the engine had no strange noises and seem to run ok..   

I wonder if you have some water (condensation) in the oil that frosted up the breather and built up the pressure.  Check for milk in any opening to the crankcase and milky oil.

[S416-8 397]

thanks for the info and will do.. was wondering about the condensation because a few days ago it was raining and now it's below 0.. 

Now to find a new cap and dipstick 

Edited Sunday at 09:51 PM by S416-8

[953 nut 63,782]

15 hours ago, S416-8 said:

Now to find a new cap and dipstick 

Need to have the engine Spec Number. Then go to the Kohler parts manual for that engine to find a part number and 

[S416-8 397]

found a cap and when I get that I'll probably change the oil for a just in case and see if it all checks out

[lynnmor 8,471]

1 hour ago, S416-8 said:

found a cap and when I get that I'll probably change the oil for a just in case and see if it all checks out

When you drain the oil of course you will look for signs of water, also take a Styrofoam cup and fill it with the used oil and let it sit for awhile.  Any deterioration of the cup indicates the presence of gasoline.

[Gasaholic 346]

On 1/26/2026 at 8:16 AM, 953 nut said:

 Then go to the Kohler parts manual for that engine to find a part number and 

Always thought D-180 had an Onan Twin (B43G or B43M)  D-160 had K341 Kohler, D-200 had Onan Twin B48....  But them Im an old fart my memory may not be as good as it used to be... (I do remember the D-250 with the renault water cooled engine as well..) 

[pfrederi 19,640]

1 hour ago, Gasaholic said:

Always thought D-180 had an Onan Twin (B43G or B43M)  D-160 had K341 Kohler, D-200 had Onan Twin B48....  But them Im an old fart my memory may not be as good as it used to be... (I do remember the D-250 with the renault water cooled engine as well..) 

Some D160 had an Onan Twin.  Others a K341 single.

 

D180 and D200 had Cast iron Kohler Twins. K482 and K532 respectively.

 

[Gasaholic 346]

17 hours ago, pfrederi said:

Some D160 had an Onan Twin.  Others a K341 single.

 

D180 and D200 had Cast iron Kohler Twins. K482 and K532 respectively.

 

OK.. Might have been regional or we just had a lot of D-160 or something.. I just remember shifting a lot of Onan engines when working on D series , typically when servicing the Sundstrand hydro pumps - usually having to replace the spline drive that bolted to flywheel , or the pump input shaft , or the control linkages or lines to and from the pump.. Mainly remember those just because it was one of the most frustrating work orders I had to deal with when working WHeel Horse (the kind that makes one cuss up a storm the whole time...)