Question for you all. I had my truck plugged in for quite awhile last night and a good portion of the morning and before I plugged it in I took it for a ride to get it up to temp (so the heater would maintain instead of just heat). Now when I got in and left I had heat then once the guage got to about the second line from C the hot air turned cold. I drove for about 5 miles and then I had heat again. Now at work tonight I plugged it in about 3 hours before I left and the same thing happened. I had the cooling system flushed and they also installed a new t stat and block heater and my cord was new last winter. I am at a loss is this normal and should I look for a "winter front" grill cover for it. Any suggestion or help would be great.

Thanks

 

By no heat, I assume you are meaning no heat in the cab from the heater, right ??

It is possible that the vacuum-controlled heater-core shut-off valve is going haywire.


What does the temperature gauge do when the heat disappears ??

 

Sorry I should of specified the heater goes from nice and warm air to ice cold. As far as the guage there is no fluctuation at all, but it will climb towards the center where the little thermometer mark is and then it goes to where it normally sits at the 4th mark above the C.

 

whats the outside temp ?

when the tstat opens its dumpin freezing ice cold water in the motor is gona getcolder thats normal

winter grill cover could help

 

Last night it was 9* and tonight it's 18*. I never gave the rad coolent a thought thanks.

Does anyone know where I can get a winter grill cover.

Thanks

 

Yup

Ryan, they still make winter fronts like mine:




Wannadiesel has posted a link to who makes them in the past. It'll fit the new grille style OK, but it's meant for ours. Also, if you're not working the truck too hard, just pull the fan off

 

In this case, would not the gauge also take a dive ??




As for the winter cover, on the wife's truck, there is a flexible card-board-looking flap that covers the area between the hood-latch area and radiator, under the hood.

I simply cut two over-lapping pieces of card-board that slide down in front of the radiator, by lifting this flap, where it merely lays against the top-front of the radiator.

When it is below freezing, and she isn't going far, I slip both pieces of card-board in there.

When not hardly so cold, or the gauge starts to show the need for more cooling air, she pops the hood and removes one of the card-board halves.

Inserting/removing only requires opening the hood and a couple seconds.

This is not visible from outside.

I have been doing this for two winters and have had zero issues with the fan-blades flexing into the radiator, overheats, or anything.

 

BK, thats what I do as well, tho I do try to center the cardboard so that there is an equal "open" area on each side of the fan.. might not matter, but won thurt either, ya know?

I am thinking a vacum issue more than anything.. the t-stat opening shouldnt cause that much of a dive in overall coolant temp as to be noticable in the heater... sounds more like the vacum switch is opening and closing, or the vacum actuated door in the heater box( the one that routes the air over the heater core) is popping shut....
have you noticed this occurring in a certain RPM range, or only when accelerating/decellerating?
Check your vacum, both under the hood at teh vacum switch located in the heater core supply hose( pass side of engine, ussualy the upper hose) and under the dash between teh heater control head and the heater box... look for loose lines or leaks...

 

Low coolant level will do the same thing.

 

cardboard and duct tape does wonders

plus you can get them at the GETITNOW store

 

Yeh check your coolant level in the rad, sounds like it's low.

 

i agree. mine does the same. when its not cold out everything is perfectly fine. But when its cold you start it up and had some hot and some cold....I wouldnt worry about it.

 

There is a vacuum valve that opens so the engine coolant can circulate through heater core, check that see if it working fully. If that is ok take heater hoses off and take a water hose that end is cut off, then insert the hose in the heater core openings. run water in one direction for a period of time and then do the other side. This will clean out the deposits in the core and you should have heat.