Alfa Romeo Forums banner

Purchased a 1986 Quadrifoglio inMay 2014

2K views 12 replies 7 participants last post by  lgbalfa 
#1 ·
The car had sat for 10+ years, it had been started and run a few miles the first 2 years. I had Eurotech in Livingston, NJ go over the car new battery, new water pump, new belts, change all fluids and replace the tires. Also the battery pan and the floor pan beneath it were gone. They welded a used floor piece and replaced the battery pan. The car was in good shape otherwise with a new top installed before it sat, mostly indoors, the exterior does not show any rust but I have not removed the lower body plastic, from the underside every thing is good. There is a small rust out at the rear of the spare tire well.
The car is silver with grey leather interior in very good condition. Some of the plastic trim pieces, license plate lights, surround for ash tray and switches are broken.
I drove the car to the Alfa convention in Detroit and home ran very well at highway speed engine was turning 3000+Rpm rountrip 1600 miles.
Inthe fall i noticed that i had no heat and the temperature gage did not go above 120F, They told me that the thermostat was not closing and the the heater control valve is broken or the core is pluged. I finally replace the thermostat waited 3 months for IAP back order to come in. Now I am trying to determine a path the clean out core blockage w/o removing.

T. McKimm New Jersey
 
See less See more
#2 ·
Welcome, and congratulations for having the patience to get your Spider set up and running. There is a lot more interaction over on the Spider-specific subforum on this board. Maybe one of the moderators could move this thread over there, where someone would no doubt respond to your question.

Do you have any pics of your Quad?
 
#5 ·
I removed the rear and front console, was able to see the heater control lever move 1/2-5/8" , the lever was not visible in the off position. I ran the engine to operating temperature, the thermostat was just replaced, 175F. The ran for about 20 minutes , holding the throttle at 1500-2000 rpm for a few minutes to increase flow. I had the blower motor on high with no apparent heat. When I checked the heater supply hose it was hot up to the firewall. The heater return hose was cold.
I plan to drain the coolant plus cleaner then disconnect the return line at the water pump. Then open the supply line at the throttle housing and attempt to flush the heater core with a water hose.
If this doesn't solve the problem than I will have to remove the heater control valve. I think if the dash removed I will have access the the heater control valve and linkage. The car has AC so i don't want to remove the HVAC module.
 
#6 ·
More likely is a failed heater valve. Inside there is a rubber diaphragm. Even though the lever is moving on the outside, no coolant may be getting through the core if the rubber diaphragm is blocking the valve. It's fiddly but the valve can be R/R'd without removing the dash & heater unit.
 
#7 ·
Eric,
Are there any threads / discussions on the replacement with the heater core in place. If I remove thee lower duct to the drivers side vent I may have access to the heater control valve but it would still be working from your back and access to the actuating rod lock screw would be tenuous. I think that if the dash is removed there would good access?

Tom
Mt. Freedom, NJ
 
#8 ·
My theory is that Alfa hung the heater unit in space and built the car around it.

Yes, the dash has to be removed for full access/removal of the heater unit. That is actually not as daunting as it sounds. You'll probably spend more time removing the center console as the dash itself.
 
#9 ·
COntinue with Heater Control Valve

Well i decided to remove the dash to continue with the heater control valve. Access to the two wing nuts holding the dash varys, onthe passenger side access thru the glove compartmentallows se of pliers to loosen ,the othe rbehind dash module is hard to dee. We found that using a 24mm 6 pt. socketand an extension works well,it also aids in tightening during assembly. I had disconnected heater return line at the water pumpand the heater feed line at the throttle housing. The first 3 photos show the dash removed, heater inlet connection,heater hose thru firewall.
The access to the heater control valve is tight, even after moving the wiring harness defroster hose and heater box elbow,the next photos show the heater control valve. Once youu have removed the 2 10mm nuts holding the heater control valve and pry it loose you pull the valve with hose forwards about 10 ", a reason you need to disconnect feed,when you replace the valve turn the hose clamp 180 deg. you need the space to get the rear nut on the stud. I removed the valve to do this before success. Also use a new gasket even though it is hard to remove, close inspection will show cracks.
I have exceeded the amt. of attachments. I will continue with the text. The new valve purchased from DiFatta Bros. was an aftermarket, i have a picture of both the control lever on the new valve had to be moved to align with the original. When you pull the heater hose forward the firewall rubber bushing will pull out, later reinstalling is easier if the coat the inside edge w/dish detergent for lubrication. Installing the rear nut is a real pain no roomlaying onyour side,you basically work blind using two fingers until your get it started. It is so tight that I was only able to use a combination and small box wrench turning 1/8 turn before a new bite. Next positioning the rod through the lock bolt , in the end I lined everything up held the lock bolt in position and advanced the rod with the lever control. I pushed the valve against the stop before aligning the lever and tightening the lock bolt.
When i removed the dash i missed the two gage module connectors, you should move the fuse block out of way, I yanked hard on the dash before I found the problem and had to later remove the instrument module and reconnect one connector that separated and reseated all the others. TOm Mt. Freedom NJ
 

Attachments

#10 ·
I will add the remaining photos.

I dis-assembled the valve it works just like a faucet valve raising the diaphram as moved to the on position, the dis-assembly shows the pin and the post with a groove, the groove covers 180 deg. of rotation the original valve only moved 90 deg.and the new valve a similar amount. This job is a pain I almost think it is worth paying a mechanic the 3 hour charge.
I was told that the way to change the heater control valve is to just remove the forward console drivers side panel and the heater elbow, it will be pretty dark in that area. Well most of the time you are working by touch.
I wish I could say it was a success, it is in that I now have heat but it doesn't shut off. I checked the new valve after moving the lever placing the valve in the off position and blowing on it. When I connected the rod i made sure the valve was at the stop.
 

Attachments

#11 ·
Ah yes! Replacing the valve is so much fun!!! I have the same problem, my heat is always on as well. I'm going to just deal with it, really dont want to endure another cussing marathon! I just put it on upper windshield vent and lever on cold and barely notice the heat.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top