6v92 overheating question (in an MCI 102c3)

JT4SC · June 10, 2019, 01:58:13 PM

Quote from: luvrbus on June 10, 2019, 10:17:45 AM

with the rebuilt water pump whom ever done the rebuild may not have the impeller tight on the shaft and the shaft is spinning but not the impeller happens all the time around here

Interesting, is that something that I can check or do I need to bring to a mechanic. There is a plate on the front of the water pump that can come off without taking the whole pump off (at least that's what it looks like to me).

lvmci · June 10, 2019, 02:49:48 PM

Hi JT, I took my bus in to get it washed at a truck stop wash, and had the engine wash because I was trying to track down some oil leaks, and a high-pressure spray turned the valve that actuates the tightness and release for the nine foot long fan belt and it was halfway open because of the water pressure I couldn't figure out why my engine was running hotter going uphill until I stumbled upon that now I check it every time I go out, lvmci...

lvmci · June 10, 2019, 03:05:28 PM

Clifford, how do you Check for damage from overheating, does oil analysis show that damage? Tom...

chessie4905 · June 10, 2019, 03:43:21 PM

If it actually hit 240, expect engine work in the near future. You need to verify temperature gauge accuracy before replacing parts. Also verify your coolant wasn't low.

luvrbus · June 10, 2019, 08:33:32 PM

Quote from: lvmci on June 10, 2019, 03:05:28 PM
Clifford, how do you Check for damage from overheating, does oil analysis show that damage? Tom...

The oil sample will show coolant from damage by heat,the next time you come I will show you some liners and pistons what heat causes and you can check those from the inspection covers

luvrbus · June 10, 2019, 08:35:21 PM

Quote from: chessie4905 on June 10, 2019, 03:43:21 PM
If it actually hit 240, expect engine work in the near future. You need to verify temperature gauge accuracy before replacing parts. Also verify your coolant wasn't low.

If the safety shut down is working it would have stopped the engine @ 215 ,@ 240 a 92 series will crack the heads 95% of the time

buswarrior · June 11, 2019, 06:34:38 AM

Analysis paralysis.

Now what does he DO?

If the coolant is staying where it belongs, you dodged a bullet.

Did we ever confirm there was/is proper coolant level in this engine? You better figure out an extremely rigid way to check the level at the same cold temp so you can measure, and you need a catch can on the overflow, or you'll freak and misdiagnose puking excess for broken engine bits...

I don't hold much stock in the temp gauge ability to accurately indicate terminal temperature, so all you know is gauge was reading higher than "normal".

Add in the ancient corroded wiring in between engine and dash gauge...

Vibration finally created a stronger path for electricity, and the shitty sender, or the shitty gauge now reads wildly wrong, instead of just a little wrong...

Sudden temp returning to "normal" suggests needle travel is not linear to temp change...

So you gauge system is totally bullshit unless proven otherwise.

Need 2 people, one to shoot the IR gun down through the floor engine access and the other to drive the coach.

The stock coach heating pipes are readily available down thru there to aim the IR gun at.

There has to be flow to get current engine temps, so open the driver's heat/defrost valve so the juice flows, and go for a drive.

Caution, the one down the back might be well advised to wear a monogoggle, windy and dusty back there...

Holler back and forth as to readings.

Find that big hill and prove that gauge has caused all sorts of unnecessary heart ache...

I am rooting for you!

Happy coaching!
Buswarrior

Iceni John · June 11, 2019, 04:34:58 PM

Quote from: luvrbus on June 10, 2019, 08:35:21 PM

If the safety shut down is working it would have stopped the engine @ 215 ,@ 240 a 92 series will crack the heads 95% of the time

Does DDEC also shut down at 215 degrees? I know there's some power reduction before actual shutdown, but I've not been able to find the shutdown temps in my DDEC manuals.

Thanks, John

JT4SC · June 13, 2019, 11:08:05 AM

Update - I decided now wasn't a good time to try to figure out how to do this myself so I took it to a diesel mechanic in town. It's looking like it's the water pump that is the main issue, he said the bearing broke so it's just spinning in place and not grabbing any water/coolant. They are also going to replace the thermostats While they are in there.
My question for you guys is I just had the water pump rebuilt about 4,000 miles ago, however that was about 10 years ago as well. Does the fact that the water pump went out again lead anyone to believe there is some other issue going on which is causing the water pump to fail prematurely? L

richard5933 · June 13, 2019, 12:43:10 PM

Quote from: JT4SC on June 13, 2019, 11:08:05 AM
Update - I decided now wasn't a good time to try to figure out how to do this myself so I took it to a diesel mechanic in town. It's looking like it's the water pump that is the main issue, he said the bearing broke so it's just spinning in place and not grabbing any water/coolant. They are also going to replace the thermostats While they are in there.
My question for you guys is I just had the water pump rebuilt about 4,000 miles ago, however that was about 10 years ago as well. Does the fact that the water pump went out again lead anyone to believe there is some other issue going on which is causing the water pump to fail prematurely? L

Water pump was 'rebuilt' - what did they actually do ten years ago? Did they just replace seals and call it a day or did they replace everything - bearings, impeller, etc.?

I'm no expert, but isn't this one of those things that does better with use than non-use? Only 4000 miles in 10 years is not much run time, and for coolant to provide protection it needs to circulate. What's your coolant look like?

luvrbus · June 13, 2019, 01:51:21 PM

Quote from: JT4SC on June 13, 2019, 11:08:05 AM
Update - I decided now wasn't a good time to try to figure out how to do this myself so I took it to a diesel mechanic in town. It's looking like it's the water pump that is the main issue, he said the bearing broke so it's just spinning in place and not grabbing any water/coolant. They are also going to replace the thermostats While they are in there.
My question for you guys is I just had the water pump rebuilt about 4,000 miles ago, however that was about 10 years ago as well. Does the fact that the water pump went out again lead anyone to believe there is some other issue going on which is causing the water pump to fail prematurely? L

People do crapy jobs rebuilding water pumps because most do not want to remove and replace the bearing because the gear needs to be pulled and the back lash on the drive gear needs to be redone,have your guy set the back lash on the gears or it will fail again

JT4SC · June 13, 2019, 04:51:31 PM

Quote from: luvrbus on June 13, 2019, 01:51:21 PM

People do crapy jobs rebuilding water pumps because most do not want to remove and replace the bearing because the gear needs to be pulled and the back lash on the drive gear needs to be redone,have your guy set the back lash on the gears or it will fail again

Sounds good, will do!

Richard, we got hit real hard in the recession and there was a couple years we just couldn't use the bus much at all. I'm thankful we've been able to use it about every month for the last couple years now.

richard5933 · June 13, 2019, 05:09:36 PM

Quote from: JT4SC on June 13, 2019, 04:51:31 PM
Sounds good, will do!

Richard, we got hit real hard in the recession and there was a couple years we just couldn't use the bus much at all. I'm thankful we've been able to use it about every month for the last couple years now.

I get it - not trying to be critical of your reasons for the low mileage. Glad you are able to get out and enjoy it more now.

JT4SC · June 17, 2019, 03:41:18 PM

A (frustrating) update: the mechanic just called me saying they located a new water pump and thermostats but now need to take the entire radiator out to change these parts. I haven't agreed to any repairs at this point, and taking out the radiator for this repair doesn't sound right to me, but I wanted to confirm that with you guys before I look for a new shop or figure out how to do the repair myself.

Van · June 17, 2019, 04:02:30 PM

What coach is this engine in?