Ice cold 454

RV and bus conversion info since 1996.

Share Your Feedback

PRINT PAGE

RV Classifieds

		2006 Keystone Hornet 27B - $18,000
		1984 MCI MC-9 - $19,950
		1993 Country Coach Affinity - $150,000
		1983 MCI 96A - $60,000
		1999 Airstream cutter 35' diesel pusher - $85,000
		VIEW ALL
		Search RV Classifieds
		Classifieds Policies
		Benefits for Dealers
		Sell Your RV
		Dealer Signup

Useful Links

RV Community

		Discussion Groups
		RV Articles
		RV FAQs
		RV Classified Ads
		Virtual RV Park
		Shop at our Store
		RV Lifestyle Books
		Rate Your RV
		AllThingsRV.com
		MyRVGuide.com
		RVMechanic.com
		Advertise With Us

BECOME A MEMBER

RV Resources

		e RV Loans
		Sculptures for your RV
		Visit Rio Rancho, NM for Winter
		RV Dealers
		RV Manufacturers
		RV Rentals
		RV Glossary
		RV Types
		RV Ratings

Ice cold 454

Home > Discussion Forum > Mechanic's Corner - Engines

email Todd

reply to message

post new message

search forums

hidden layer

ATTENTION: All Postings that advertise items for sale will be deleted from the Discussion Forum. You may post sale items for free in the Classifieds section. Sign up now.

All Messages in Thread	Author	Date
Ice cold 454	Todd	3-12-06
28’ Allegro with 1995 Chevy 454 that only provides heat when idling. I get 148 degrees out of the heat vent when idling then drops to 70 degrees when driven a few miles or with engine rev’d for a few minutes The problem started about 5 years ago. Have put on 20,000 miles since the problem started. The engine has never overheated and the temp gage runs consistently around 210. The engine runs like a champ – it just doesn’t heat! Here’s what I’ve done over the past 5 years and have run out of ideas: 1.The coolant supply line comes from the back of the block - goes to the bottom connection of heater core. 2.The coolant return line is on the top connection of the heater core and connected to the top of the radiator. 3.Checked/replaced thermostat and radiator cap 4.Checked/replaced heater control valve to make sure it's working 5.Checked for correct vacuum pressure to the control valve 6.Checked the outside of heater core box to make sure it's sealed completely to fire wall. 7.Checked the blend air door in the heater control box to see that it's moving and not disconnected inside 8.Checked the nipple coming out of the engine for blockage 9.Replaced supply and return hoses 10.Checked for a possible air lock in the heater core by bleeding the return line 11.Installed clear tube in supply line – small bubbles at idle – all foam at higher RPMs 12.Coolant block tester – indicated low level of CO2 in coolant 13.Magnafluxed heads – no cracks, some warping - planned heads and replaced 14. Replaced - water pump and heater core 15.Still have small bubbles at idle and turns to foam at higher RPMs What’s next?
Re: Ice cold 454	Ruben Siegfried	3-14-06
Sounds like the waterpump is in cavitation. (pumping air) Why? I don't know maybe the lower radiator hose is collapsed. check the hose and see if the sping inside is still there and the hose is firm and not limp like a stepped on plum. Hope this helps some problems are really strange yet surprisingly simple.
Re: Ice cold 454	Jack	3-21-06
I would suggest checking vacuum lines. Your heater control works off vacuum. At Idle the vacuum is high. The vacuum can drop off on acceleration or on hills. This will stop the air flow, thus no heat from the vents. The place I would start would be the heater control valve. Pull the cable off it and turn it so your getting heat from your vents, no heat turn it the other way. Once you get heat, place some hay wire around the valve so it will stay, and take your rig for a short test drive.
Re: Ice cold 454	Todd	1-29-07
Last summer I replaced hoses and rechecked the vacum lines - Still no heat? What in the world could this be? * small hole in the block or cylinder head? * blockage in on of the waterjackets? * they missed a crack in one of the heads? Help?