Townace Pickup 2Y gas smell in cab

I have a 1995 Townace DX flatbed pickup with the 2Y gas engine. It runs very well, but after a drive there is a strong gas smell that accumulates in the cab.
If I air out the cab and let the truck continue sitting for a couple days, the fuel smell does not come back - so it seems to be related to when the engine is running.
I don't notice the smell while driving or idling.
Sometimes, after driving and then letting it sit for a little bit, it will take longer to start. Perhaps the carb is flooded?

Any tips on how to troubleshoot this are greatly appreciated. I am tracking down a 2Y repair manual right now...

Thanks!

Fuel leaks, especially on hot engines always end badly, its just a matter of time.
More than one van has been lost to an engine fire

Fuel damper is the #1 suspect but it can be other things just as easily.
It needs to be inspected and repaired BEFORE it is run again.

Thanks for the reply - and the words of warning. I am not planning on running it until I solve this...

I just checked the charcoal canisters - there are two of them right next to each other. Looks like one off the carb and the other off the fuel tank? The one off the fuel tank seems pretty clogged up, air is not moving freely through the vent. The one off the carb is flowing smoothly.

I've read that a bad/clogged charcoal canister can result in excess fumes... Could this be the cause?

I've inspected the engine pretty thoroughly while it's running (I turn it off before the engine warms up) and I cannot see any fuel leaking anywhere...

Regarding the damper - I believe you are referring to the fuel pulsation damper? I will try and locate/inspect this part. I'm assuming this is a pretty common feature on most toyota engines? I'm not seeing it listed in my 2Y manual. (EDIT: is this part specific to fuel injection based systems? my truck is carbureted)

Thanks again.

We only got FI versions and yes a fuel damper is part of that parcel.

Being carbed all bets are off, fuel rarely leaks in a dripping sort of way, put another way, if you can see fuel leaking, you got some serious stuff going on.

Fuel is volatile and it evaporates exceptionally well, even more so when things are hot.

Start at the tank and follow the lines to the front, inspect them well, I know they are metal (mostly) but they can still corrode and vent fumes for a long time before actually leaking.

Canisters can indeed become contaminated, happens when people are trying to squeeze in those last 3 cents cause the gas is cheap this week.
Pre '90's they could often be revived, (its just activated charcoal) no idea what you've got on your hands tho.

If you eliminate the lines and the canisters that would only leave the carb.
Look for tell tales, fuel leaks are very hard to spot but if bad, they will leave a "discolouration" on metal.
You may also have a fuel cut solenoid and possibly more than one, pay close attention to hose, while there is an O-ring on the business end I have also seen them seep thru the body.

Being carb'ed should mean it has a mechanical fuel pump? If so, thats another potential source of a leak.

Thanks for the tips - I'll look around for discoloration or worn/corroded lines.

My evap/charcoal canisters are plastic and don't look like they were meant to be serviced - which is unfortunate as finding new replacements is not going to be easy.

I've seen some people cut them open and replace the charcoal, then glue them shut afterwards. I might try that if I have no luck with compressed air.

Considering they are plastic they are probably not serviceable, some of the older metal ones were, to a degree.
Finding out how you're canisters are supposed to operate, would be key, before condemning them.

Have you tried Toyodiy.com?
You can look up by market/model and might find a part number that way.
Armed with a part number, same site will list if it fits any other vehicles, potentially widening the search.

There's enough JDM trucks on here, maybe reach out to some other members that source parts out of Japan and see if they can help out?

Also check out megazip.net a direct from Japan OEM parts site.

Good luck

JDM

Thanks for the tips on parts. I've already inquired with jp-carparts.com and they don't have a replacement available. I have a request in with megazip, and have reached out to a friend that imports/has connections with local JDM suppliers.

Some more details:

As I mentioned, there are two charcoal canisters, mounted right next to each other. Both have similar construction - two pipes on top, one on the bottom. The 2Y manual states to test by blowing air into the larger intake port on the top. If working properly, air should flow without resistance from the smaller port on the top and the larger vent on the bottom.

The first canister - which is receiving from the engine compartment - passed this test fine. The second canister does not. The top output ports on both canisters are merged into the same line. The input port (larger) on the second canister appears to be connected to a metal line that runs to the fuel tank. This second canister seems to be specific to the Townace, as it's not mentioned in my VW Taro 2Y manual.

More details about the second canister:
Air does move through it, but there is a lot of resistance - not flowing freely. However, the larger port does allow air to be sucked backwards through it. This leads me to believe that it could be stuck or clogged.

These canisters do not seem to be manufactured anymore, and I don't want to put in a used one. I'm considering cutting it open where it was glued together and attempting to service it. I've seen enough examples of people succeeding with this to feel confident that I can glue it back together. The other option is deleting the evap canister - but I'm not sure how to best do that without interfering with the existing vacuum system.

I have noticed that when opening the fuel cap there is a woosh - which leads me to believe that the tank is not venting properly. I have also notice when fueling the pump shuts off pretty often - another symptom of venting failure...

Any thoughts/insights are greatly appreciated. Thanks again!

attached are some details from megazip & my 2Y manual

https://www.megazip.net/zapchasti-dl...tube-17741573#

Attachment 11781Attachment 11782

quick update - i tried bypassing the suspected canister - ran the fuel vent away from the truck with a long hose and idled the truck until it warmed up.
after turning it off and letting it sit for a few minutes the fuel vapor smell returned to the cab... so i guess i can rule out the canister.

First of all, I have no experience with the 2Y engine, so this is purely theoretical, but as the smell comes áfter you shutdown the engine ánd it is harder to start after it sat for a while. Could it be that the fuel in the carb, just boils away after the engine is shut down? When the engine is running, the air passing through the carb, keeps it cool, and probably prevents this, and the vapors would be burned anyway. But with the engine shut down, it could heat up, and boil away, and cause a smell. I think the carb does have a small window to check the fuel level in the carb. If this drops substantially in the minutes / hour after shutting down, you know at least where it comes from.
If that is the case, I have no idea how to solve this though.... maybe the carb has some kind of vent tube, or it is overheating, because of a missing spacer between the engine and the carb... no idea..

We need to back up the bus here.
We can imagine all sorts of issues that may be contributing but as you know HOW to create the problem, diagnosis should be easy.

Get it running and then shut it off but dont walk away.
Crawl under and start using your nose to see if you can identify where the smell is emanating from.
Start at one end and work to the other, first pass should be a quick one just to see if you can identify a gross area.
Once that area is identified (front or back) redo the test and focus on items in that area.
Using a length of hose can make your nostril MUCH longer and make tight spots easier to interrogate without disassembly

When the vehicle is moving fumes tend to get blown away but when it sits, those fumes will be left to rise and the cab is the highest point so it makes sense that the fumes will gather there, but it doesn't mean thats where they are emanating from.

I recently had an issue with Suzy, fuel smell in the cab, on the highway only and it was intermittent.
When it would happen, it was so strong I thought it must be the fuel rail leaking and I wasted a lot of time with that assumption
(I also skipped the fundamental smell test, due to my false assumption)

In the end it was the vent line on the tank, I only found it because I was out of options and dropped the tank out of desperation.
That is the problem with assumptions, they cloud judgement.