Moroso intercooler tank (cap) issue

My issue is the cap doesn’t seal 100%. When under boost fluid pukes out through my hood vent on to the passenger side of the windshield. I noticed many have had this issue with various aftermarket brands. Anyone here swap out the cap with success? If so, which one worked for you? Thanks…

Molon Lave said:

My issue is the cap doesn’t seal 100%. When under boost fluid pukes out through my hood vent on to the passenger side of the windshield. I noticed many have had this issue with various aftermarket brands. Anyone here swap out the cap with success? If so, which one worked for you? Thanks…

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Mine is doing this as well…..In for the replies.

In fact, I thought my pump was dieing thinking the coolant was getting too hot and blowing out due to pressure. I’m putting in a new pump just in case…

That doesn't sound right. The tank should not be seeing boost. You need to start digging a little deeper. If you don't have proper coolant flow, the heat from boost will boil whatever coolant is still in the cooler. Also, check for leaks in the system and make sure you have good fluid flow. For every pound of boost, 10 to 15 degrees can be added to the intake air temperature. If boost is finding it's way into your fluid system, you have much bigger problems.

The stock tank never did this for me. It seems heat/pressure related for me. My IATs were very high as well. My situation might be different than OPs. My pump also had issues running when trying to jump it.

2003RedfireVert said:

The stock tank never did this for me. It seems heat/pressure related for me. My IATs were very high as well. My situation might be different than OPs. My pump also had issues running when trying to jump it.

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I had no issues before either. I replaced the stock one cause the plastic tank cracked

2003RedfireVert said:

Mine is doing this as well…..In for the replies.

In fact, I thought my pump was dieing thinking the coolant was getting too hot and blowing out due to pressure. I’m putting in a new pump just in case…

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Well thats no good. OP, his cap is brand new as well as the lid and gaskets. That seems to me like pressure is getting too high. Where is it spitting out the fluid from exactly?

Could it also be maybe over filled? Not enough room for the hot water too expand, causes high pressure and out the cap it goes?

FleeMan said:

Could it also be maybe over filled? Not enough room for the hot water too expand, causes high pressure and out the cap it goes?

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I think is mine is this and a combo of heat. The IC pump, some distilled water, and a lower level will probably fix mine.

Mine was coming out of the gasket portion I believe. The cap itself wasn’t leaking.

Would recommend checking/replacing the O rings for the intercooler adapter under the blower. If it's only spitting fluid under boost air is probably bypassing those O rings and pressurizing the system.

OP, check the bolts around the lid. Several of mine were lose and if applied any sort of pressure with the air hose to the system with the lid closed fluid came out between the gasket, Lid base, and bolt holes.

I know I’m not leaking coolant via boost. Mine tank lid is just letting any pressure out via the lid/gasket.

Good luck Op!

FleeMan, I’m not worried! Something I should checked before putting it on. Easy fix! I love the extra capacity I have.

2003RedfireVert said:

OP, check the bolts around the lid. Several of mine were lose and if applied any sort of pressure with the air hose to the system with the lid closed fluid came out between the gasket, Lid base, and bolt holes.

I know I’m not leaking coolant via boost. Mine tank lid is just letting any pressure out via the lid/gasket.

Good luck Op!

FleeMan, I’m not worried! Something I should checked before putting it on. Easy fix! I love the extra capacity I have.

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Well damn man, I was sure I snugged them down enough. Guess they just needed a little more. Glad it was something simple!

FleeMan said:

Well damn man, I was sure I snugged them down enough. Guess they just needed a little more. Glad it was something simple!

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They could have backed off too. Who knows. Easy fix so I ain’t worried.

I had an issue with my moroso cap rusting and upgraded to the pro works cap. Been on the car for 4 years with no issues.

OP, tightening the bolts around the ring fixed my issue. It holds pressure now until the lid starts to lift which is I believe is normal once it hits its pressure rating. No longer does fluid/air leak out the sides. Good luck!

My cap issues was related to a bad pump.

FleeMan said:

Could it also be maybe over filled? Not enough room for the hot water too expand, causes high pressure and out the cap it goes?

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Only filled up half way

2003RedfireVert said:

OP, check the bolts around the lid. Several of mine were lose and if applied any sort of pressure with the air hose to the system with the lid closed fluid came out between the gasket, Lid base, and bolt holes.

I know I’m not leaking coolant via boost. Mine tank lid is just letting any pressure out via the lid/gasket.

Good luck Op!

FleeMan, I’m not worried! Something I should checked before putting it on. Easy fix! I love the extra capacity I have.

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I had to tighten the bolts for the gasket cause they were a little loose as well. That’s where coolant was escaping at first, now it’s escaping from the cap