dyermullet

I found one of the leaks. Water is seeping in on the PS on a body seam up high under the dash. Also leaking around the top of the heater/ac box to the dash. Also leaking in through the speaker wires (speakers crummy added to the door panels) that are closed in the door weather stripping (easy fix cut the wires).

Doug thank you. From that illistration I am missing more than just the bottom bracket. I am also missing the two through bolts from the tray direct to the inner fender and thr inner fender itself. Thanks again

Thanks for the replies and the link. Does anyone have a picture of the bracket installed? I am trying to visualize where it goes. Currently my battery tray is only bolted to the core support, and I have struck 3 bricks under it to hold up the battery while I have been working on the car. I have read multiple times how the chevelle inner fenders will swap into the 1st gen monte. Is there some kind of inner fender extension at the front to make up the length difference? I need to look at the DS of the car to see, it is still intact. Thanks again.

I did some searching here and found out I am missing the battery tray support bracket. That looks like this: https://www.opgi.com/monte-carlo/KR20066/ Does anyone have a picture of how this bracket mounts to the car? I keep reading referneces to it bolting onto the inner fender. My PS plastic inner fender is all broken and missing under the battery tray so I think that is where this bracket must bolt to? Thank you.

I updated the thread with some details. I will keep filling in the blanks.

Hello everyone. I have been getting a lot of great advice from everyone on here. Thank you. 71 Monte Carlo factory air. The blower motor switch is bad, it was arcing internally and now has failed. I temporary bypassed the switch so I can get the fan to run. The AC works decent on the car, but after a few days I am getting arcing in the mode selector switch, MAX AC, LOW, Heat, Defrost etc. Does anyone repair, or recondition these? Or do I have to purchase a reproduction? I haven't looked at the AC/Heater control closely yet, but I can see the sparks from the front so I know it is bad.

Ok I am going to go for it. Will be next week probably. I will report the results.

I have a good running Vortec 5.7L i pulled from a 1998 chevy suburban. I know about the vortec specific intake, no mechanical fuel pump provision etc. My question is about the oil pan. Does anyone know if this truck oil pan will fit my 1971 monte carlo? If not does anyone know what oil pan I need for a 1 piece rear main seal block? Thanks in advance. I am getting close to finishing up this swap. So I thought I would update the thread with some details for future search. I will try to update with some pictures and part numbers, and put in better order. I swapped a complete L31 from my 1998 chevy suburban (I need to upgrade to a 3/4 ton truck, so I decided why not), into my 1971 monte. The car is a 350 2 barrel factory AC th350 trans. My goal was to reuse as many pieces as I could (keep the cost down), and stay somewhat stock appearing. I pulled the L31 from the suburban, cleaned, painted chevy orange, and installed it as it. Intake: I purchased an Edelbrock Performer Vortec intake thinking it would be the best choice because this is just a cruiser, and I wanted the most hood clearance. It turns out the Performer intake doesn't have any provision to use coolant to warm the manifold, while the Performer RPM and GM performance parts manifold both do. So if I was to do it again I would purchase one of those. The performer intake doesn't have the correct bolt hole locations to mount the rear upper AC compressor bracket. I reused the stock thermostat housing, the mounting surface on the intake is taller which required me to modify the stock upper alternator bracket. Timing cover: I keep the stock L31 plastic timing cover because I just used the engine as is, it didn't have any major leaks. The plastic timing cover is too large and does not allow the power steering pump bracket to be installed. The solution is to install a traditional tin timing cover. Right now I just want to drive the car, so I am going to try an allen grove PS bracket. edit: Allen Grove PS bracket worked perfect. It allows the factory AC bracket to work with no problem. Stock length PS and AC belts. Only negative to using allen grove PS bracket and the factory AC bracket is can't check the PS fluid while engine is running. Have to reach into the belts to reach dipstick. Oil pan - Stock truck pan fits the car no problem. Fuel pump - I installed an inline fuel pump I saw referenced online. I also remember selling these at the auto parts store back in my college days. I will post a part number but universal inline pump fits 70's datson and mazda pickups. Revised Coolant bypass - I used 3/8" heater hose from intake to a T on the return hose from the heater core. Vortec 350 blocks are not drilled for the internal bypass directly to the water pump. Valve Covers - I reused the truck valve covers. I don't know the best combination yet. The DS oil fill tube interferes with the factory AC compressor. I swapped them DS for PS but accidently broke off the extended length oil fill tube when installing the engine. I might try to get a TBI truck valve cover because it doesn't have the extended oil fill. Exhaust manifolds - I used the 1971 manifolds, so I could bolt the existing exhaust back in. I couldn't install the spark plug boot heat shields because the mounting holes exist but were not tapped on my L31 block. I might go back later and correct this, but didn't want to spend the time. The manifolds fit, but the spark plug boots are very tight to the manifold, so I think the spark plug location may by slightly different than the old heads. If this turns into a problem I may try to run the truck manifolds or rams horns or other. (as of Feb 2017 has not been a problem). Distributor - old worn out HEI distributor that was already on the car. (had to change distributor gear to match the factory roller cam) Spark plug wires - used a mixed set of wires I already had. Most are too long need a better set. I used the vortec hold downs to keep the wires cleanly mounted. Carb - I am giving the 625 cfm Street Demon carb a try, I like Q-jets but I wanted to give this carb a try after seeing at a vendor display this summer. And it was half the price of a good Q-jet. The Street Demon carb vacuum fittings is in the way of the threaded hole on the intake for vacuum. So PB is on one 3/8" port, PCV on a second 3/8" port and all other are on the 3rd smaller carb port (vac advance, th350 modulator, HVAC). Will have to see how that works. edit: Carb works great. even the idle mixture screws were perfect. Any change resulted in a drop in vacuum. Only downside is the carb is blocking the rear vacuum port on the intake. I had to plug that. I have power brakes on one carb port, PCV on second carb port. And that left all other accessories (hvac, trans, distributor vac advance) on third carb port. If I ever have the intake off i might drill and tap another vacuum port. Throttle linkage and kickdown linkage - I used the lokar carb bracket. It fit perfect. I used lokar trans kickdown cable (my original started leaking at trans) and lokar throttle cable. Trans -reused the TH350 no problems that I can find. Starter - I used the factory 1998 vortec starter. Battery Cables - I redid the battery cables reusing parts from the suburban, and my new positive is a cable I had. Negative from battery to the block, added ground from battery to body, and going to add another braided ground from body to frame. Used some factory 98 hold downs to keep the cables looking cleaner. Added 2 relays for the fuel pump and the electric choke, ran power directly off the battery through a fuse. Motor Mounts - reused 1971 style motor mounts. Replaced bad DS mount. Future will be cam swap, new timing chain, tin/aluminum timing chain cover, and maybe manual trans.

Thanks for all the help everyone. I will report back what i find.

The car is getting water in from just sitting in the rain. The leak is bad. I had a big pool of water standing in there after it rained.

I havnt pulled any windshield trim yet. I will pull it and inspect.

Any water down the windshield causes a leak at the same place on both sides of the car.

Bump. I updated the original post with a picture and more information.

Removal of the dash pad was very simple, and I was able to access the heater/ac controls through there. So far I didn't break anything.

Thank you. I will take my time on it.

Is that the best way? I cant find anything in the factory manual showing is removal. I have the factory service manual is that the best source for electrical scematics? The 1971 drawings are not very good. I work with electrical prints everyday, i think a guy doesn't would struggle to use those diagrams.

71 monte My blower motor doesn't work, I found the fuse was blown. I changed the fuse out and I can hear electrical arcing when moving the selector. It is also very rough to actuate. How do I get access to the unit? I found Bruce has posted this picture: https://picasaweb.google.com/110808817090254771768/HeaterCoreReplacement?feat=directlink#5337554503508271650 It looks like the assembly is bolted on to the back side of the dash. Can I remove the dash pad to gain access to this? Thanks

Thank you very much that is exactly what I needed. My seats are missing the hole and the white plastic guide, where the belts pass through. Your picture looks exactly how I assumed the factory configuration. I decided to ask here before I just cut a hole in my seats. The belt install was very straight forward. Only problem is the 4 bolts for the high mounted point, the bolts were not dimensionally to spec. I had to run them through a die to remove the black oxide coating and correct the threads. After that I was able to thread them all the way in by hand, no tools. I am satisifed with the way they look. Tomorrow I will modify my seats and finish installing the female portion of the belts. Thanks again.

71 monte carlo. factory bench seat. My car was missing the front seatbelts when I purchased. I am installing the MCC three point harness. I need help on the routing of the female part of the belt. The only orientation I can find is to run it over the back of the bottom part of the seat and then inbetween the top and bottom seat halfs. It doesn't seem correct to me, to have to go all the way around of the back of the seat. I have been looking for an opening in the seat bottom to thread it through. Does anyone have a picture of bench seat car how the center part of the belts route?

I am 100% confident it is not heater core leaking.

Arizona car. Everything looks nice and clean with the carpet removed, no rust. That is what made me suspect rain coming in through the window, after I couldn't recreate the leak. I pulled the carpet out so I can dry it before it starts rusting. It is not antifreeze just water (yes the radiator has glycol in it). AC works on the car but there is some electrical problem right now all the hvac is dead, until I jiggle some wires under the hood. That will be my next troubleshooting. What is the normal path water gets into the air box, if I run water down the windshield would that be the path to test it?

Hello everyone. I purchased a 1971 monte carlo last week from a coworker. It has mostly sat for the last week because I had been busy with work. Tonight I was changing the door locks and found that the PS front carpet was soaking wet. I hosed the car down for a long time with the garden hose and couldn't get it to produce a leak. It hasn't rained here in over a week. My friend had the car parked in his driveway with the windows cracked, and we had 4 days of very hard rain I am thinking maybe it got wet before I puchased it. I pulled the carpet and padding out tonight so I could dry the car out. Are there any common places these cars leak? I was thinking maybe the heater and AC box drain might have been plugged but the amount of water I put down the windshield it would have shown up. Thanks EDIT: I identified the leak, now I need to find the source. It is leaking on both the DS and PS, but significantly worse on PS. Water is running down the corner where the firewall meets the "kick panel" for lack of a better word. I took a picture so it would be easier to identify. I circled the area in red where the water is running down. It is leaking at same place on both sides. What would cause this leak? Windshield seal? Edit 2 Replaced the windshield that fixed those leaks. Identified a source on both sides of the car, PO had added speakers to the doors and ran the wire past the weather striping. This allowed water to run down the wire then drip inside the car past the gasket surface. I cut and removed the wires which fixed that problem. If i run the garden hose down the cowl on the ps i can still get water to leak. It is coming in through a body seam up high behind the dash next to firewall and the outside of the body. Also it is leaking where the dampner for recirculating air is. I am going to start parking outside and see how bad these two leaks really are. I suspect under normal rain storm will not have a problem. Have to flood the car with garden hose to create. In the future i will pull the fenders reseal the air box and redo body sealer.