hello...I recently purchased a 1996 960 sedan. I recently replaced cylinder head and realized the heater core was disconnected and hoses clamped together. I assume the heater core leaks although there are no signs of water or antifreeze stains on driver side carpet and best of all no damp smell!!

My question is...would it damage my cooling system to reconnect the hoses to the heater core and run some type of "stop leak" through the system to see if that solves the problem before ripping the entire dash/console and just about everything else..to replace core...?

Thank you for your help....this is my first volvo...and so far so good. it had 236,000 miles on it when i bought it...however the interior and exterior of the car were in pristine condition and it rides like a dream with plenty of power especially now with new head,valves,springs etc...

 

Symptoms for heater core leak, besides coolant smell inside and wet carpet, is fogging of the window. Wet carpet can be mistaken with a leak from the clogged cowl drain, which weeps inside.

Does the heater valve leak?

Bar's leak has worked for me but others curse it. Most likely it won't damage the cooling system, and most likely would not fix the heater core leak. It will collect at the bottom of the radiator, which by the way might need replacing too, because core and radiator kinda have the same life-expectancy.

To be honest, now that you have the new head, I would replace the heater core. Job is relatively easy, but takes time. Dedicate 12-16 hours as the first time. Shop Hours are 8.6 hrs.

I would also replace the coolant hoses everywhere and the Heater Valve, and use Zerex-05 coolant (NAPA).

 

thank you...the radiator, aux fan,timing belt,water pump,serpentine belt....were all replaced with cylinder head replacement...just wanted a break from ripping car apart...this time from the inside....oh well ...better get started...any suggestions on a good aftermarket heater core....just not in the financial mood to pay 400+ bucks for oem...thanks again

 

No way. A good Nissen unit should be about $ 140-150. I would get other brands if they are all brass. Aluminum ones don't heat up very quickly. Cores with plastic necks are questionable.

I think Spectra sells for about $ 110 all brass. I got one from a guy on eBay selling overstock from FCP all brass. I think it was like $ 80.

Like I said, I would make sure to replace the Heater Valve as well. They leak over the Transmission Connector causing wire shorts. Some just explode. Don't go Scantech or URO on that.

I am not sure if you replaced the oil cooler (Big-Mac looking) hoses. Buy hoses (5/8" IIRC) by the foot at local parts store.

Good time to also take oil cooler apart, clean it, change the gasket and o-rings (about $ 15) from Tasca. You would need an axle socket (42/43 mm IIRC) to loosen the big bolt for the cooler.

 

Hello, thanks for all the advice....finally replaced the core today...man what a job...wouldnt wish this on anybody...all has gone well so far...no parts left over..lol. just wanted to know what hose goes where...they were clamped together when purchased the car. From the right side of the control valve there is a hose that was connected to the bottom of the two hose recepticals of the old heater core...the top hose connection was left open. I noticed that the two hoses that are clamped together originate from the back of the engine on the left side...just wondering which hose goes to the top of the heater core connection ..and which one goes to the left side of the heater control valve?

Unrelated question: does anybody know what size headlight wipers go on the 1996 volvo 960? i found some on autolampsplus but the 960 wasnt listed...they have 5,6,and 8 inch blades...

 

Hose WITHOUT the valve spliced into, goes to the top receptacle (outlet). Valve -> bottom receptacle (inlet).

If you are still confused -- follow outlet hose (<- top receptacle) -- it connects to a metal line which goes to the coolant return manifold -> pump. This is not easy to see.

Inlet (with Valve spliced into) comes from the head of the motor.

I don't recall size of headlight wiper blades. Check FCP. Just make sure they come in pairs or singles. Some people order 2 and end up with 4 blades.

 

Thank you for ur quick response...however still confused as their was no top outlet hose connected to the old heater core when i purchased car...however i guess i can feel around down below the cam sensor on left side of rear engine to see if i can feel a hose going into a metal line as appose to engine block inlet?

 

That's how bypass is done. Again, hose with Valve in-line gets connected to lower receptacle of heater core. Hose WITHOUT Valve goes into the top receptacle.

If you post a photo I will mark your photo and post back.


Both hoses connect to respective metal lines in the vicinity of Cam Pos Sensor. I think you are better off trying to look from underneath. Find the coolant metal manifold (spider-looking) and you should be able to see the heater return line. Hose from bottom of reservoir connects to this spider too.

 

Thanks sooo much. found it....it all makes since now...all i really had to do was disconnect the two hoses from each other and it was obvious then what hose went where just judging by the length of the hoses themselves...but I did as u suggested and looked from underneath and found the metal hose line going to the radiator...and i was all set.

Thanks again for all ur help...u guys are awesome!!

BTW ...and this maybe answered in another thread with regards to ignition harness..mine is frightfully frayed and brittle and i think is just a matter of time before I get stuck someplace or start misfiring if I havent already..

any suggestions on repairing those wired that ride along the top of the valve cover?

 

Search this forum -- there was thread recently with the COP (Coil-On-Plug) wire problems and how to fix them.

What heater core did you end up getting? Did you use Zerex-05?

 

I purchased the nissens from Europarts for $136+tax..everything seems to be working fine....its nice to have a heater now. Although I live in California..I live in the san bernardino mts 5500+ altitude..so it does get a little brisk this time of year, just had 6 inches of fresh snow a few days ago..again thanks for ur awesome advice..don't know what i would have done without ya!! I'M going to check the threads for cop wire problems and see what i come up with.. I've been to "Bills Page" and viewed his 150.00 solution..which is currently unavailable....don't really have 150 bucks right now anyway..so hopefully i will find a more budget friendly solution...thanks again..dejr

 

I don't know who is Bill's page. I know Dave Barton.

Regardless, some wire cleaning, splicing / crimping (not soldering) and heatshrink should suffice.

 

thats what i meant....knew it was a common name....apparently he is out of stock...any other idea's?....i guess i could check out a few local salvage yards...? not really any ideas on the posts i read...

 

This is not something you want out of junked cars. That's why it was not recommended by myself or others.

Other ideas? You mean other than repairing or replacing them?

Did you read the other thread about where to buy wire terminals?

 

Thanks for u suggestions...I didnt see any posts with regards to buying new wire or where. Question: are the connectors(from the 2 wires to the coil) re useable? could I simply remove frayed wire from connector..crimp,cut repair and heatsink..and reinstall into connectors?

 

Yes. Yes.

 

Part of the problem is the heat around the wiring from the engine, esp. the top valve cover holds the heat around the top wires.
I run my car with it removed, not the nicest looking motor with it missing, but saves the wiring harness!