Question about 1990 GMC Sierra
Replaced the heater core and its not heating up?
The #1 cause for this ailment is low coolant. Be sure the air was burged from the system so that the heater core is not airlogged. #2 check for broken or disconnected vacuum lines under the hood. The heater air cond. system is dependent upon vacuum to actuate the dampers in the airbox. Rarer: check the heater hoses for restrictions, I have seen good looking hoses delaminate internally and pinch off the coolant flow. Somewhere between #1 and #2 I should mention the thermostat. But if the thermostat is at fault the temp guage will never reach the normal range.
First, my disclaimer:
I have a much older projector, but the way they are constructed hasn't changed a lot to my knowledge.
An excess of dust can shorten the life of electronics, it's a given. But the majority of these sets are allowed to collect dust for many years of operation before any problem occurs.
I sense that you may instead be asking about cleaning the lenses and mirror. Actually, the mirror, since it faces somewhat at a downward angle in these sets tends to stay clean. the lenses however, face upwards, and do get quite dusty, causing a blurry picture, with ghostly images on the screen at their worst.
To clean the lenses on most RCA sets I've seen, the screen must be removed. Allow the set to cool and voltages to dissipate for 30 minutes before beginning this process. There should be a removable panel beneath the screen, usually retained by screws on the backside at each end. REmoving the panel will expose the screws that keep the screen in place at the bottom. With the screen removed, the lenses (there are three) will be quite obvious. I clean mine with typical glass cleaner and SOFT paper towels. PAY ATTENTION not to allow any liquid to drip into the projector below or you may disable the projector unit possibly causing damage that must be repaired. If you are successful at the lens cleaning you will have restored the picture quality to like new.
If you find my suggestions to be helpful, please share with us some details so that others may benefit from knowing the whole story. Thank you!
Posted on Dec 19, 2008
Confirm water ,coolant flow threw heater hoses if your correct . i would suspect you need thermostat
Posted on Dec 19, 2008
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
Here's a link to this great service
Posted on Jan 02, 2017
Tips for a great answer:
Feb 14, 2013 | 1994 GMC Suburban
Feb 20, 2011 | 1994 GMC Suburban
Feb 25, 2010 | 1995 GMC Sierra
Oct 09, 2009 | 1985 GMC Suburban
Jan 19, 2009 | 1989 GMC Suburban
Jan 19, 2009 | GMC Envoy Cars & Trucks
Jan 11, 2009 | 1999 Chevrolet Suburban
Dec 17, 2008 | 1989 Chevrolet Suburban
80 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: