custom hood vent wets sensors -need help

I bought a 90xj with a stroker engine a few months ago. The previous owner had cut holes in the hood and put two vents over the hood to help cool the engine.

After the last big rain the transmission wouldn't shift out of first With some help from this forum I diagnosed the problem as a wet throttle position sensor, and indeed the transmission worked after the xj dried out.

However the vents are right above all the components near the back of the hood on both sides of center line, and I'd like to either protect the sensors and any other electrical or other component sensitive to water, or else figure out a way to cover the vents when it rains (even when I drive)
or to drain the water under the vents so it doesnt soak my electrical sensors

Any simple, ideas.

Assuming you want to retain the use of your vents, why not fabricate a gutter of sort to attach below the vent so that water runs off to a safer location. Alternatively you can simply make a cover out of aluminum or even plastic to sheild your sensors

XJguy.

I was having a similar problem with snow getting through mine, causing drifts to form under the hood on top of my TB. I tried using magnetic floor vent covers but they weren't strong enough.

I ended up changing out the metal vents for cheaper ( :laugh3: ) plastic ones with tabs on them that allows for them to close. Cost was about $2 ea.

lapaul said:

Any simple, ideas.

Click to expand...

Hood Vent , near the bottom of the page he explains how to deal with water...

If your hood vents are flush with the surface of the hood (i.e. not louvered) then a simple strip or two of magnetic sign material should cover those up with ease! If you really want to low-buck (read: free) this idea, go to any of your favorite self service car washes, and ask the attendant-on-duty (if there is one) if they have any signs that got knocked off in the "automatic" wash. (some corporate folks forget to remove their companies' magnetic signs from the doors before they go to the car wash) I usually get a half dozen a year! And its totally free. :laugh2: :spin1: And better yet, those strips of sign material will stay put up to, say, 80-85 mph! (I've tested them)

THIS IS AN ABSOLUTELY BRILLIANT IDEA, I NEVER WOULD HAVE THOUGHT OF IT

THANKS

vents aren't flush with surface, but they are removable, and I'm sure if I can find a magnetic sheet of metal I can remove the vents when not in use or in the rain, and put them back when I need to.

I'll see if I can find some non Louvred vents or maybe even some flat steel with vent holes in it that I can permenantly mount and cover with the magnetic steel when I want to







If your hood vents are flush with the surface of the hood (i.e. not louvered) then a simple strip or two of magnetic sign material should cover those up with ease!

WHERE DID YOU GET THE PLASTIC VENTS THAT CLOSE

DO THEY COME IN DIFFERENT SIZES

LynchMob said:

I was having a similar problem with snow getting through mine, causing drifts to form under the hood on top of my TB. I tried using magnetic floor vent covers but they weren't strong enough.

I ended up changing out the metal vents for cheaper ( :laugh3: ) plastic ones with tabs on them that allows for them to close. Cost was about $2 ea.

Click to expand...

I got mine at Canadian Tire. I'm sure walmart and most hardware stores would have 'em south of the border.

They come in at least 2 or three sizes (standard floor vent sizes).

I had riveted the metal ones down...these I just used RTV sealant.

BTW...be sure you get the one's that are low profile...they are less common but won't obstruct anything down below.

I managed to snag two magnetic covers for the vent hole at a local sign shop

total cost $12 ,

Even though you say they'll stay on to 85 mph , I'd like to have a way to
make sure they stay on, yet can be removed when I want to put a vent in
(or uncover the vents if I find some that are flush to the hood)

Any suggestions as to how to make sure the magnetic strips don't fly onto the windshield in high winds and or high speeds

lapaul said:

I managed to snag two magnetic covers for the vent hole at a local sign shop

total cost $12 ,

Even though you say they'll stay on to 85 mph , I'd like to have a way to
make sure they stay on, yet can be removed when I want to put a vent in
(or uncover the vents if I find some that are flush to the hood)

Any suggestions as to how to make sure the magnetic strips don't fly onto the windshield in high winds and or high speeds

Click to expand...

You put the magnetic covers on the outside then open your hood and duct tape the edges from underneath. Should hold up for a while like that.

The magnetic covers are 12" wide by 18 " long, they extend about 6 inches
below the vents toward the front of the vehicle. The did the job during the last rainstorm (no water got in under thehood)

Ilve decided to drill holes in the hood just below where the each vent ends and put a bolt and washer through the magentic cover and the hood. These bolts should should hold the magnetic cover down when I'm driving in rain and wind (if the blow up they will flop down again) yet should let me swivel the cover around to the front to uncover the hole so I can put the
vent in when I need to use the vehicle in dry weather. Its a bit cumberson, to swivel the covers, and put the vents in and back out but its the simplest solution I could come up with.

Fabricating a drain system under the hood seems a bit too complex to me.

So far I haven't been able to find vents that will install flat, If I can find such vents then I won;t have to take them out when I put the magnetic covers over the vent holes.

XJ91 said:

You put the magnetic covers on the outside then open your hood and duct tape the edges from underneath. Should hold up for a while like that.

Click to expand...

lapaul said:

So far I haven't been able to find vents that will install flat, If I can find such vents then I won;t have to take them out when I put the magnetic covers over the vent holes.

Click to expand...

Is there a way to rivet the vent from underneath? This way the vents are not protruding over top the surface of the hood?

I would think you could take the covers off the vents when you ae driving. No rain should get in when moving. You just have to worry about the rain when its parked. My vents are farther twards the front of the hood and I cant see how when driving on the high way water it going to go down into them. So just take them off when you are going on the highway if you are worried about them blowing off.

I have been running 2 hood vents (hood cowls off of YJs) since July of last year. One is directly over the intake manifold / throttle body and the other is over the distributor. It rains and snows a fair amount in AK and I have yet to experience any problems with water getting into any of the sensors. Could you just clean and silicone all the connections really good? There are some guys up here that silicone the distributor cap to the distributor for water crossings. If it works for that I would assume that you could do the same thing for the TPS, MAP, etc.

I am going to put vents in my hood as well (it gets pretty hot in phoenix in the summer...). Why not put the magnetic material under the vent in the engine bay??

The swivelling vent covers made of sign material work well and are easy to use. The white covers on the the black xj hood look kinda cool.

When I get a chance i'll try to silcone the connections, but I'm a little wary of depending on just that in a heavy rain (while not driving) after my previous bad experience of the ransmission not shifting after the throttle position sensor got wet.

LynchMob said:

I was having a similar problem with snow getting through mine, causing drifts to form under the hood on top of my TB. I tried using magnetic floor vent covers but they weren't strong enough.

I ended up changing out the metal vents for cheaper ( :laugh3: ) plastic ones with tabs on them that allows for them to close. Cost was about $2 ea.

Click to expand...

What kind of plastic ones and where can/did you get them ???