I have a rainwater leak into my UK HDJ80 (1996, 1HD-FT, manual). No rust worth talking of, and it's not the old sunroof drains issue - sunroof sealed up years ago during the overland build; drains seem to have been removed; leak occurs without pouring water on the roof.
The windscreen and bonnet/hood have both been replaced fairly recently so I am suspicious of these. However, when I pour water around the windscreen and wiper area, the water seems to flow into the engine bay at the corner, and down inside the wing/fender. In the engine bay this soaks the insulation, which can't be good for keeping rust away. Water appears to pool behind the bulkhead - or between it and the inner wheelarch - and this will continue dripping for some minutes under the wheelarch. At the same time, inside the vehicle in the footwell, this water starts to seep through the seam between the floor and the body. There doesn't appear to be any rust and it doesn't appear to be a simple hole - it looks like it just seeps through a few inches of the join.
Any ideas what's going on? I'd love to see some pics of how the seals around the bonnet/hood should be, as I'm suspicious that they haven't all been refitted.
Replacing the windscreen requires to adhere the gasket to the body and ALSO adhere the gasket to the windscreen. Most windscreen replacements for other vehicles is a one-step process and is commonly done incorrectly on our trucks. This always results in a water leak.
Replacing the windscreen requires to adhere the gasket to the body and ALSO adhere the gasket to the windscreen. Most windscreen replacements for other vehicles is a one-step process and is commonly done incorrectly on our trucks. This always results in a water leak.
True, but don't he is saying leaking to the inside common with the windshield improperly installed, but the seal around the bonnet and water in the engine bay. If I read that correctly.
1. Right side corner
2. Left side corner
3. Right side corner closeup
Does your truck leak more on the right side?
Looking at your pics, it appears that the rubber weatherstrip that runs along the back of the firewall is under the cowl cover on the left side, but not on the right. On my truck it is tucked back under the cowl on both sides. If water runs into the gap between the hood and cowl, it should be channeled off to the sides and flow into the drip channels on the top of fenders (under the hood) and run towards the front of the truck. At least on your right side, because that weatherstrip is not tucked under the cowl, it looks to me like that water would miss the drip channels on the top of the fender and run right down inside of the fender along the firewall.
This may only be part of your problem. As was mentioned earlier, proper installation of the windshield (adhesive between glass and gasket, and then between gasket and body) is critical to preventing leaks. Additionally, any debris plugged drains at the bottom of the fenders or rocker panels will result in water finding its way into the footwells.
So I have lifted but not removed the panel between hood and windscreen ('wiper panel'?) - not clean, obviously, but there was no debris. They'll have cleaned this out when changing out the windsceen I'm guessing.
What type of adhesive would you use for the windscreen gasket?
I think you're right about the positioning of the seal which runs under, and forward of, the wiper panel. That's primarily why I was looking for a photo. One side is different to the other, so I think this make sense - I'll go change it. Subtle but I think it could be key. Should this seal be helped out a little with, for example, silicone? It is the left side which has the leak - passenger's side for me. This side is slightly downhill on my driveway.
Additionally, any debris plugged drains at the bottom of the fenders or rocker panels will result in water finding its way into the footwells.
@mingles how can I access these drains to clean them out? It would make sense if they were blocked after 7 months of driving through Africa! The other side had to be replaced after an idiot drove into us when stationary.
The easiest way for you to find pictures is to use the search feature (upper right hand corner of this page) as there are much better pictures than I can provide. Use the search term “rocker drains” and choose search area as “this forum”. You will get lots of threads.
Basically the drains are three or four slots that are along the bottom of the rocker pinch weld beneath the front doors. Use something wide and flat like a cable tie to push up into them from outside the truck. Work it around until you have dislodged all the debris.
thanks, eventually found them. No water in mine at all - bone dry.
For other newbies like me who chance upon this thread: rockers are the bits below the doors and the drain holes (on a '96 80, at least) are on the inside, under the vehicle - so get under and look up and 'out'. 3 round rubber covers about 35mm diameter along the length of the panel. Prise them out gently with a screwdriver. [EDIT: turns out I was wrong, see below for corrections including photos]
My issue may be simply the positioning of that seal along the front edge of the wiper panel. I'll try moving that tomorrow and checking with a hosepipe.
Thanks all, really appreciate you helping me out - especially @mingles. Thanks @Kernal for the adhesive link.
OP - I think you’re confusing the floorpan plugs for the rocker drain slits.
FWIW, my initial thought was like @jonheld - we’re hitting a point where unless you have a urban, garaged 80 - all the rest of us should pop the cowl cover & see how much foliage has collected & shop-vac it out.
The Toyota factory used liquid Butyl sealant when installing both the front, and rear rubber windshield gaskets on these trucks. Below you'll find links to not only liquid Butyl sealant, but also the correct tool to apply it with too. Amazon product ASIN B000K40PGA
I've just had another check of the whole area and the windscreen seal doesn't appear to have been sealed/bonded to the body in any way. Running my finger under the seal (outside) from the top corner to the bottom led to a fair bit of water coming out - and it's been dry for a few days now here in the UK. I think I'll take a hairdryer to it when I get myself some sealant so as I'm not sealing moisture in there. The new windscreen was installed in Cape Town - they don't get much rain there compared to the UK...
I've moved the cowling seal to go over the top of the engine bay rain gutters. I stuck a long skewer down between the inner wing/fender and the bulkhead to check where it came out - and as suspected that is where I pictured the drip from, under the wheelarch. So all good, as designed.
In summary, I think there are/were a couple of things going on here:
windscreen seal most likely the cause of rainwater making its way into the footwell
cowling seal running under the engine bay rain gutters were causing water to run into the engine bay. This was a red-herring really, though I suspect it would cause rust longer term.
