8.1 Engine Shroud

[Rocket Heart]

I recently experienced the rear 4 spark plug's being broken due to overheating in the rear of the doghouse on my Itasca 07, Suncruiser. In examining the engine there is a shroud (for lack of a batter termanology) that comes from the firewall and drops down to the top of engine.

My firend is an automotive engineer for McClaren (same as the racing McClaren's) and we came to the conclusion it would really open the airflow to the whole engine compartment, thus reducing the heat build up on the doghouse.

Question being does anyone know the intended purpose of this covering??

[rgrstndgby]

Question being does anyone know the intended purpose of this covering??[/quote]

Hi Tom, if you are refering to a heavy rubber like shield, it is "critical" where it is. It forses most of the air passing thru the grill to be directed thru the radiator, coolers. condenser etc. It can't be removed or altered without causing alot of trouble with that flow. Others on here can address plug/plug wire overheating, but "ya gotta" leave the shield in place...rgr...

[DriVer]

Quote:

Originally Posted by Rocket Heart Question being does anyone know the intended purpose of this covering??

The purpose for the fabric that is attached from the upper firewall to the top of the cool pack is there to direct the flow of air coming in through the grill. It is essential that the fabric remain in place in fact if more can be done to block all the openings around the sides of the radiator this would improve the cooling.

What needs to be cool is the engine coolant. Running air over the top of the engine does nothing to cool the spark plugs and failures will continue to occur. Personally, I have not had this type of problem on my 38G Adventurer.

What you are looking for on your vehicle is called a "Vent Kit." The vent kit is comprised of 2 pieces of 3 inch tubing which are attached to scoops positioned in the front of the vehicle. The air that comes in through the scoops is directed toward the 6 & 8 and the 5 & 7 spark plugs. The tubes are terminated to open end and the air discharge simply flows onto the vicinity of the spark plug boots.

This kit is available under warranty. Please see your local authorized service center.

The use of after market plug wires such as Taylor Extremes has been a choice that Workhorse owners have often made who have encountered this type of issue as well as others who were simply looking to obtain better performance.

[Rocket Heart]

Thank you gentlemen - appreciate the response. Have contacted
workhorse who in turn told me to contact my local dealer - which I did seeing as he was the one who found the bad plug wires - the dealer reply was that my plug were "broken" not burned and therefore probably not eligible for the kit.

Let you know.

[Rocket Heart]

Ya know on second thought I'm not at all happy with either of those alternatives - leave the air dam on it burns the rear plugs - not acceptable. Take the air dam off and risk the chance of doing more damage to the cooling system and or condensor etc., again not acceptable.

Are all Workhorse chassis designed like this, with an air dam for cooling, or just for Winnebago's? It seems my 07 Suncruiser's grill is far below the level of the air dam for the air dam to be of much use? Most of the air goes under that point - there is nothing to push it up to the dam.

It just amazes me what we accept as - part of owning an RV. Poor engineering on someone's behalf is to blame - the fix? Plastic tubing - to get more air the plugs of which I am now told should be cooler if the air dam was doing a better job of cooling the engine. My temp guage has always read the same - below 1/2 hot - think that's about where most vehicles run too.

Got some more investigating to do.

[max49]

I tucked my flap back a long time ago. Haven't burnt any plug wires since and have'nt noticed any side effects except it is easier check engine and tranny fluid.

[DAN L]

[QUOTE=Rocket Heart;496263]Ya know on second thought I'm not at all happy with either of those alternatives - leave the air dam on it burns the rear plugs - not acceptable. Take the air dam off and risk the chance of doing more damage to the cooling system and or condensor etc., again not acceptable.

Are all Workhorse chassis designed like this, with an air dam for cooling, or just for Winnebago's? It seems my 07 Suncruiser's grill is far below the level of the air dam for the air dam to be of much use? Most of the air goes under that point - there is nothing to push it up to the dam.

It just amazes me what we accept as - part of owning an RV. Poor engineering on someone's behalf is to blame - the fix? Plastic tubing - to get more air the plugs of which I am now told should be cooler if the air dam was doing a better job of cooling the engine. My temp guage has always read the same - below 1/2 hot - think that's about where most vehicles run too.

ROCKET HEART:
that "1/2 hot" is 195 deg f. per my scan gauge II. it does have a 195 degree thermostat installed. i have been advised not to change the thermostat. the dash gauges are not scaled accurately. per my workhorse chassis manual (p 50), they are not even supposed to be scaled accurately. the stated purpose of the gauge is to "provide a warning of any rapid change in temperature from the normal reading of that particular gauge". such a deal!

[hamguy]

When I got the rig in '04 (an '02 Cuncruiser) the rubber air dam was broken and only half effective. I never fixed it and it finally fell off 2 years ago. Our travels are mostly mountain and summers. After 30,000 (71,000 on the odo) miles, I have never overheated or had any problems with cooling system.

[Rocket Heart]

ROCKET HEART:
that "1/2 hot" is 195 deg f. per my scan gauge II. it does have a 195 degree thermostat installed. i have been advised not to change the thermostat. the dash gauges are not scaled accurately. per my workhorse chassis manual (p 50), they are not even supposed to be scaled accurately. the stated purpose of the gauge is to "provide a warning of any rapid change in temperature from the normal reading of that particular gauge". such a deal![/quote]

That amazes me too! Wonder if any of the other guages work the same - pretty much useless until it's too late - what are they thinking??? My question to you is - who informed you of this information about the guage? Workhorse? It helps with my complaint to the powers that be.

[TandW]

The bottom line here is system efficiency. If the fabric, boot, shroud, baffle, bulkhead, firewall is not mechanically intact, that is, there is no place for hot air to return forward, passing thru the cool pack in an endless inefficient cycle, then all engine fans will be forced to operate at increased duty cycles. This requires horsepower which in turn requires a higher combustion rate which lowers system efficiency which increases cost to operate. It should be realized by all that higher doghouse temperatures over longer periods will be experienced if proper once thru air flow is not maintained. The FCA or Fan Clutch Assembly will not engage and roar nearly as often as temperature excursions will be fewer if the system is intact. Those who climb mountains regularly or who drive in high summertime temperatures will benefit the most from properly maintaining the area around the coolpack.But, I do not think that even those who drive in Alaska would want to be breathing exhaust fumes or any other sort of engine leakage when doghouse air is allowed to recycle forward and perhaps enter the heater inlet. A good reason to keep it intact! Also, do not forget that front air dams extending below the "Bumper" help to generate "Low Pressure" immediately below the engine when there is forward motion. This is an area that should be kept intact, but that can sometimes be improved also with flat sheeting that extends back to the front-most chassis cross-member. Keep your cool, folks and Good Luck!!!

[DriVer]

Quote:

Originally Posted by hamguy Our travels are mostly mountain and summers. After 30,000 (71,000 on the odo) miles, I have never overheated or had any problems with cooling system.

hamguy, Well taking a chance like that on such an expensive engine for the lack of a less than $100.00 part is almost like never getting hit by lightning. Ahhh .. check that - we did get hit by lightning.

[stearn]

I had our " engine miss" repaired while in Florida. I took it to a dealer in Ft Pierce. I had two wires with the ends broken. They replaced all the plug wires under warranty. I asked them to check to see if I could get the duct work to cool the plug wires. I was told that I did not have burnt wires, and before workhorse would authorize a fix I would have to have the burnt wire problem twice. They couldn't tell me what caused my wires to break. I will be out of factory warranty soon so if it happens again then what.
I will be watching your post and any others that mention bad wires. I hope my problem was a permenant fix , but I doubt it. Oh! I was told that the duct fix was not cheap.

[Rocket Heart]

That's exactly what I am afraid of - the royal run around!! I am going to figure out how to send this whole post to WH. Will let you know.

[stearn]

Thanks! Lets hope they won't leave us out to dry!