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EH ventilation plenum to firewall sealing
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Hi
I have an EH that leaks into the cabin when. Everything from windscreen to drain tubes has been replaced. I have now diagnosed is as leaking between the "plenum chamber lower panel" (under the ventilation grill that the wiper shafts poke though) and the engine firewall. There is a layer of black body sealant between them, and its cleary leaking.
My question is, how do you get these apart for resealing? Do you have to pull off the front fenders? Are they in fact separable at all without grinding welds?
Matt |
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EH's will leak in that area due to only a couple of issues. 1. Rust holes in the plenum chamber behind your glove box & dash areas. 2. The drain tubes are blocked & the water is flooding through the fresh air vent. 3. The drain tubes are cracked letting water dribble onto floor. 4. Heater core, if fitted, is leaking. In the case of a Premier heater, either the core or the heater valve has a leak. I have never identified a leak around the seams of the plenum chamber area. Most likely rust unfortunately. Utility8  |
utility8
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I would say with most certainty - rust. I have fixed many EH's for rust in this area. If it is old or rare - Cut it! http://www.ehlimo.com.au/ |
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Rank: Member
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Thanks guys
I'm almost certain it's the seam. The tubes are new, there is minimal rust in the car, and if you lie under the dash (no floor lining at this stage, and no heater radiator) and get my friend to pour water on the outside, you can see it coming in the seam. From the outside, you can see that the sealing compound has deteriorated. |
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The plenum outer, middle and lower panels are all welded together, with the outer mated to the widscreen lip, and the top of the firewall, with the middle panel sandwiched inbetween. They are all spot welded together with about 120 spot welds. I have dissassembled the entire compilation of the plenum before, repaired and re welded. The set is designed with the lower panel being a complete bowl with no seams, so as to eliminate any leaks from original design. Great when new, but as there was no paint between the panels (cant spot weld painted panels), they rust. The design does not allow leaks unless water is introduced under disproportionate amount or pressure compared to regular rain and washing. Rust allows leaks. If it is old or rare - Cut it! http://www.ehlimo.com.au/ |
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EH ventilation plenum to firewall sealing
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