My vented coolant reservoir cap has never quite fit right. As a result, coolant keeps evaporating, and every other week I have to top it off.
The only cap I find at parts stores is a Dorman unvented cap. I bought one and it fits great. Now I'm wondering if my first cap is original or not. Maybe a past owner put the wrong cap on there. I don't want to use the unvented cap if the car should have vented.
SSEi owners: what do you have: vented or not? You can tell by looking at the cap. Unvented is a solid flat cap. Vented has two tiers.
Ken_W
Should SSEi's have vented coolant reservoir cap?
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Ken_W
- Posts like an L27

- Posts: 634
- Joined: Sat Aug 14, 2010 9:54 pm
- Year and Trim: 2000 SSEi
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Should SSEi's have vented coolant reservoir cap?
2000 SSEi "Gypssei" - 206k miles - Light Bronzemist Metallic - stock
1999 Grand Am GT - 168k miles - Red - stock DEAD -- transmission died
2004 Pontiac Montana Ext 2WD - 207k miles - Blue Black Metallic - stock
1999 Grand Am GT - 168k miles - Red - stock DEAD -- transmission died
2004 Pontiac Montana Ext 2WD - 207k miles - Blue Black Metallic - stock
- harofreak00
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Re: Should SSEi's have vented coolant reservoir cap?
The original cap is not vented, the tank has its own vent built in. I've never even seen a vented reservoir cap.
The coolant is not evaporating, you probably just have a leak.
The coolant is not evaporating, you probably just have a leak.
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler
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Ken_W
- Posts like an L27

- Posts: 634
- Joined: Sat Aug 14, 2010 9:54 pm
- Year and Trim: 2000 SSEi
- Location: Lake Orion, MI
Re: Should SSEi's have vented coolant reservoir cap?
Thanks Haro -- I'll put the good-fitting new cap on and see if I still lose coolant. You may be right about there being a leak, but I want to rule this out first.
Ken_W
Ken_W
2000 SSEi "Gypssei" - 206k miles - Light Bronzemist Metallic - stock
1999 Grand Am GT - 168k miles - Red - stock DEAD -- transmission died
2004 Pontiac Montana Ext 2WD - 207k miles - Blue Black Metallic - stock
1999 Grand Am GT - 168k miles - Red - stock DEAD -- transmission died
2004 Pontiac Montana Ext 2WD - 207k miles - Blue Black Metallic - stock
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BRUTE FORCE
- SLE Member

- Posts: 48
- Joined: Tue Jul 21, 2009 6:41 pm
- Year and Trim: 2000 Pontiac Bonneville SSEI
Re: Should SSEi's have vented coolant reservoir cap?
If your original cap does not quite fit well, just wrap some electrical tape on the threaded part on top of the reservoir and then screw on the cap, it should fit nice and tight.

