Leaking water pump replaced. Now no heat and overheating?

10

Asked by Mar 28, 2015 at 07:10 PM about the 2004 Chevrolet Express

Question type: Maintenance & Repair

My 2004 Chevy express 3500 box truck was leaking water out of what appeared to be
the water pump. I purchased a new pump and thermostat. After replacing the pump and
filling the radiator I started engine to come up to temp. Never seemed like stat opened,
water level only went down slowly. After engine temp started climbing over normal I
turned on heater and no heat at all, just cold air.  With engine climbing above operating
temp I was thinking new stat is no good but with no heat I'm wondering if something
else?

3 Answers

30

Just by taking a wild stab at it, I would guess that you have a TON of air in the system. If there is enough air in the system, it basically becomes vapor locked, especially in the newer engines. Best way maybe to remedy this would be to take the thermostat back out, fill the block VERY slowly with antifreeze where the stat goes until its full, put the top radiator hose back on the stat housing, then fill the hose just enough that you wont spill it everywhere when hooking it bck up to the radiator, then fill the radiator VERY slowly also. That should do the trick. They also make thermostats that are guaranteed not to stick closed if your worried about that. Hope this helps

3 out of 3 people think this is helpful.
10

Thank you. That makes sense. I will give that a try.

1 out of 1 people think this is helpful.

What TY said is correct . I experienced same problem. I took the hoses off. Filled as much as I can slowly with coolant . Started the van. Let idle with few revs all is good

Your Answer

Add photo

Related Questions

  • Over heating 4 answers

    I have a 2008 Chevy express van 5.3 vortex engine. About this time last year I replaced the water pump and put a new thermostat in twice. Well it started running hot again two weeks ago. I replaced...

    2008 Chevrolet Express

    -

    Maintenance & Repair

  • Why engine is overheating right after alternator was replaced?! 1 answer

    Right after alternator was replaced the engine is overheating at maximum. "Engine hot, AC off" is appearing on board. "Service battery charging system" is still appearing on board, when the engine i...

    2008 Chevrolet Express LS 1500

    -

    Maintenance & Repair

  • neither the cigarrette lighter nor the auxillary power outlet work. have changed the fuse so its not that. 1 answer

    plugged in a power converter so i could use a drill to remove screws from a part of the wheelchair lift (too hard to do with screwdriver). think i must have blown something because it quit. replaced...

    2001 Chevrolet Express G1500 LT Passenger Van

    -

    Maintenance & Repair

  • 8100 vortec motor 5 answers

    I recently purchaaed a 2001 chevy express that started making what i assumed to be liftre and rocker arm noise rather suddenlly while driving it home it stalled and seemed to freeze up the motor u...

    2001 Chevrolet Express G3500 Passenger Van

    -

    Maintenance & Repair

  • Still overheaating after having water pump replaced 2 answers

    After having water pump replaced the heat no longer blows out and the engine is still overheating

    1996 Chevrolet Impala 4 Dr SS Sedan

    -

    Maintenance & Repair

Express

Looking for a Used Express in your area?

CarGurus has 5,483 nationwide Express listings starting at $1,200.

ZIP:

Search Chevrolet Express Questions

Chevrolet Express Experts

#1 tenspeed
tenspeed
Reputation 260
#2 dizybren
dizybren
Reputation 200
#2 Sarai Sanchez
Sarai Sanchez
Reputation 200
View All

Related Models For Sale

Used Chevrolet Express Cargo
57 Great Deals out of 13,421 listings starting at $3,499
Used GMC Savana
3 Great Deals out of 1,504 listings starting at $2,500
Used Ford E-Series Wagon
42 Great Deals out of 1,522 listings starting at $1,500
Used Ford E-Series Cargo
90 Great Deals out of 3,110 listings starting at $1,495
Used GMC Savana Cargo
19 Great Deals out of 4,607 listings starting at $2,295
Used Chevrolet Silverado 2500HD
317 Great Deals out of 27,006 listings starting at $1,250
Used Chevrolet Silverado 1500
1,748 Great Deals out of 169,330 listings starting at $1,800
Used Ford E-350
219 listings starting at $2,495
Used Chevrolet Suburban
358 Great Deals out of 19,010 listings starting at $2,295
Used Chevrolet Astro
232 listings starting at $1,500
Used Ford Transit Cargo
102 Great Deals out of 19,894 listings starting at $11,500

Used Cars For Sale

2017 Chevrolet Express For Sale
2,189 listings starting at $22,683
2016 Chevrolet Express For Sale
3 Great Deals out of 1,319 listings starting at $19,999
2015 Chevrolet Express For Sale
401 listings starting at $15,498
2014 Chevrolet Express For Sale
329 listings starting at $7,995
2013 Chevrolet Express For Sale
9 Great Deals out of 158 listings starting at $9,999