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dreamchasers
06-07-2009, 06:29 PM
I have noticed that in the XL version of Prevost coaches, some have one or two rows of louvers cut in the rear engine compartment doors (like the the louvers cut in the side engine battery access door). My Country Coach does not have these louvers. My engine temperature runs from 195 to 210.

Does these cut louvers in the rear engine door help with the engine cooling? Am I missing out on something good?

Hector

garyde
06-07-2009, 07:40 PM
It certainly allows more air and venting. I think it would help with the bedroom as well.

Joe Cannarozzi
06-07-2009, 08:51 PM
They did that with the introduction of the 60 series I thought.

None of the 8-V's have them that I am aware of.

Jon Wehrenberg
06-08-2009, 07:29 AM
The vent slots in the doors are not a converter responsibility. Back in the day when the 8V82 engines were 475 HP guys wanted more HP so the rage was for individual owners to reprogram the engines. The only problem was that more HP creates more heat and if the heat cannot be removed the computer removes HP. So when the added HP was needed most, like climbing a long hill, it was not available because there was not enough ventilation to get rid of it and the DDEC cut back on the HP to manage temps.

Detroit had to approve the engine installations, so when Prevost offered the increased HP one of the things they did was to increase the vent openings in the RH side door. I believe the ventilation openings in the doors surrounding the engine area are all Prevost original equipment and have been part of the installation approval process that Prevost and Detroit go through. I also believe the converters specify the size and location of vents in the bay doors for such things as the generator bay and that the bus is delivered to the converter this way.

That's my recollection from one of the seminars put on by Prevost about 17 years ago.

Gary & Peggy Stevens
06-08-2009, 09:49 AM
That's my recollection from one of the seminars put on by Prevost about 17 years ago.

That's pretty good recollection Jon, do you remember what you had for lunch last Friday? :D

Gary S.

Jon Wehrenberg
06-08-2009, 10:07 AM
As a matter of fact I do. We had Ruebens that I prepared.

There smart ass. Now what are you going to pick on me about?

(In the interest of full disclosure I remember because they were made of some great bread and pastrami that we brought back with us from our recent trip to western NY.)

dreamchasers
06-08-2009, 10:15 AM
Jon,

Thanks for the info. I will be sure and add these vents when the repaint comes.

Hector

PLSNTVLE2
06-08-2009, 10:24 AM
The big question is "Engine Temperature". Hector stated 195-210 degrees operating temp. Is this a good range?
I believe this is an acceptable engine temperature and the additional louvers would probably not have any affect unless other contributing factors such as OTR compressors or a dirty radiator would influence the engine compartment temps.
As mentioned, I would believe the louvers would take some pressure off of the bedroom temperature.

The engine operating temp. should be controlled by the thermostat and the two speed radiator fan. I don't think anything below 195 F is what Detroit would like to see.
I think I would be concerned with anything outside of that range.

Jon Wehrenberg
06-08-2009, 10:45 AM
Terry is correct. However, one thing to consider is the radiator condition.

The fan and thermostat are set to maintain what may appear to be high temps, but Hector's listed range seems very reasionable. I think the first stage fan cut in temp is 204 and the second stage is 208.

A plugged radiator may not be detectible unless someone can determine by observing trends to see how often the fan runs in the second stage. A driver needs to be very concerned if the temps do not cycle up and down while climbing a long steep hill. We can observe the fan clutch going between the stages by seeing the temps hit their peak and then drop back a little, and then climb back up repeating the cycle. If we don't notice that, indicating the radiator is working efficiently then consider having it checked, possibly having it flushed, or to an extreme having it recored.

The standard vent openings in our engine side and back doors are more than adequate unless the converter has installed stuff to block the flow of air, or there are some flaps added or missing because air also goes out beneath the coach. I do not know the Prevost position on converter added full width rear mud flaps. I do not know if they help or hinder air flow. I do know on some later models there is a baffle beneath the radiator that needs to be there so flaps do have an influence.