need help changing thermostat
Thread Starter
Racer
Joined: May 2012
Posts: 269
Likes: 0
need help changing thermostat
got throttlebody loose but got vacum lines passing over rear bolt of thermo hsg. hard plastic tubing aready broke off one side of the soft rubber that connects it to something, the one that didn`t break is in the way. what can i do? need to pull it off so i can reattach broken line.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
got throttlebody loose but got vacum lines passing over rear bolt of thermo hsg. hard plastic tubing aready broke off one side of the soft rubber that connects it to something, the one that didn`t break is in the way. what can i do? need to pull it off so i can reattach broken line.
Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
take off the tb, it's the best way...this is a simple job, but a pain in the azz nonetheless.
buy a hose and bypass the throttle body, saw off and file down the nipples
i feel you can splice rubber hosing for the busted plastic
buy a hose and bypass the throttle body, saw off and file down the nipples
i feel you can splice rubber hosing for the busted plastic
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
I got an 86 ... not much change to 87. Yesterday I replaced my radiator ... 4 Hr job. Found out after that the either the water pump wasn't working or the T-stat was stuck closed because it began to overheat and the top hose was cold.
Today I replaced my T-stat PITA 5 Hr job without removing the TB... only 2 bolts but you can only get 1/8 wrench turn using a combination wrench turn ... switch wrench over ... turn ... The back one wasn't so bad but the front one was a bear. The bolts are 1 1/2" long.
I used a 160 degree Robershaw with a 3 hole air bypass ... no burping. Afterwards my temps have never been better ... no hotter than 185 running the A/C driving for about an hour.
Good luck.
Today I replaced my T-stat PITA 5 Hr job without removing the TB... only 2 bolts but you can only get 1/8 wrench turn using a combination wrench turn ... switch wrench over ... turn ... The back one wasn't so bad but the front one was a bear. The bolts are 1 1/2" long.
I used a 160 degree Robershaw with a 3 hole air bypass ... no burping. Afterwards my temps have never been better ... no hotter than 185 running the A/C driving for about an hour.
Good luck.
Last edited by 3D-Aircrew; Nov 4, 2012 at 04:44 PM. Reason: added info
Thread Starter
Racer
Joined: May 2012
Posts: 269
Likes: 0
the lines i`m talking about connect to something under front of plenum. i need to unplug it to get to bolt but not sure how to get it off. don`t need to be breaking anymore stuff. i will not even be able to back that bolt out with it in the way. its the connector. i broke one line flush with it, need to get it out so i can drill out broken piece. anybody got any idea how it comes off? and the radiator drain, have to get to it from under car?
Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
the lines i`m talking about connect to something under front of plenum. i need to unplug it to get to bolt but not sure how to get it off. don`t need to be breaking anymore stuff. i will not even be able to back that bolt out with it in the way. its the connector. i broke one line flush with it, need to get it out so i can drill out broken piece. anybody got any idea how it comes off? and the radiator drain, have to get to it from under car?
the plastic lines go into a rubber 90 to the tb, just pop it off of the tb when you take it off,
drill 2 small holes in the stat, don't rush the job, take your time and it will fall in place, sounds like you are hurrying it , and are worse for it.
take a good look at everything before beating and yanking on it.
Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
one line goes to the egr valve, don't yank this hose loose or you will be taking off the plenum to put it back,
it is t'd off of the connector you are talking about, forget all that , take the tb and you will see everyting, air cleaner off, maf off, inlet tube to tb off, tb off, upper water hose off, stat housing off, you will see...
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Thread Starter
Racer
Joined: May 2012
Posts: 269
Likes: 0
but i can`t get to the rear bolt wih this thing in the way. TB is out of way but this cotton picking connector is in the way. guess i`ll have completely romove the TB so i can see under plenum. job usta take 1/2 hour if there was a carburetor there.
Safety Car
Joined: Oct 2008
Posts: 4,022
Likes: 30
From: Los Angeles CA
that's what i said take a deep breath and take off the tb, by pass it while you are messing with it and do it once, drill the stat,make is a 2 day job, instead of a 5 min job, what's the rush?
Thread Starter
Racer
Joined: May 2012
Posts: 269
Likes: 0
ain`t in no hurry. just stimied by this connector over the back bolt. guess i may be only one here who had to deal with this, otherwise car would be up and running by now. well i`ll just watch some football and deal with it tommorow.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The EGR solenoid is held on the rear thermostat housing bolt by a bracket. There are two plastic vacuum lines attached to a rubber connector block on the EGR solenoid. One goes to the EGR valve and the other goes to the bottom of the throttle body (that's the 90° connector that others have mentioned). The plastic lines pull out of the rubber connector block or you can unplug the block from the EGR solenoid. You can buy the plastic vacuum lines at any auto parts store.
The throttle body is very easy to remove to get access to the front thermostat housing bolt:
1 - Unclip MAF from air filter housing.
2 - Loosen plastic bellows clamp at the front of the throttle body and remove it with MAF attached. Just lay it off to the side with the MAF cable still attached.
3 - The throttle body is attached to the plenum by 4 10mm bolts. You can just unbolt it and move it out of the way with everything attached (except for the vacuum line on the bottom -- it's too short, so you have to unplug it).
The throttle body is very easy to remove to get access to the front thermostat housing bolt:
1 - Unclip MAF from air filter housing.
2 - Loosen plastic bellows clamp at the front of the throttle body and remove it with MAF attached. Just lay it off to the side with the MAF cable still attached.
3 - The throttle body is attached to the plenum by 4 10mm bolts. You can just unbolt it and move it out of the way with everything attached (except for the vacuum line on the bottom -- it's too short, so you have to unplug it).
Thread Starter
Racer
Joined: May 2012
Posts: 269
Likes: 0
thanks cliff, now i know what i`m dealing with. soft rubber plug was a bitch to pull off, it was held on by rust on the metal nipple on the solenoid. thermo turned out to be original. car still takes a while to warm up but faster than before. needed to change coolant anyway. got car from dealer with no service record. instead of trying to use radiator drain, didn`t want to risk breaking it off, i rigged a hose to my shopvac and snaked it down to bottom of radiator tanks. the drain sits a couple inches off bottom anyway
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Once you have the TB out of the way a socket gets the front T-stat bolt out easily. An open-end wrench get the rear one and that bracket holding the EGR solenoid just comes right up with the bold so you don't need to unplug all those vac hoses. Plus the vac lines running to the TB are now loose and easy to move out of the way.
That drain plug is a beotch to get to. I recently did the TB coolant bypass when doing the 160deg T-stat switch and had to turn the front wheels as well as jack the front end to access the plastic drain plug...
That drain plug is a beotch to get to. I recently did the TB coolant bypass when doing the 160deg T-stat switch and had to turn the front wheels as well as jack the front end to access the plastic drain plug...
Race Director
Joined: Sep 2003
Posts: 16,838
Likes: 341
From: Database Error Indiana
I never open radiator drain plugs. Get clear plastic tubing and stick in in there and syphon it out. Once you learn your way around the L98, this will be a 45 minute job. Dont be surprised if one of the Tstat bolts snaps off also. Drill, tap, install stud and move on. 