4x4Wire TrailTalk

Carb and vacuum issues

Posted By: Tuxedo_Ranch

Carb and vacuum issues - 03/22/19 08:56 PM

Howdy Everyone,

This is my first time opening a thread with a question, so it may be messed up.

I am the proud owner of an 87 Raider I picked up for $240 on an insurance buy back. It has the 2.6 motor with 5-speed manual.

Something with the carburetor isn't right, it is very sluggish and will go through a tank of gas in about 100 miles. I've read a lot about changing the stock carb for a Weber, but which one exactly? Does anyone have a used Weber carb they would like to sell, I only plan to run this motor for about a year then replace it with a Diesel.

Also, I would like to remove all the vacuum lines that are not needed, does anybody have a vacuum chart showing what's needed and what's not??

It's been a long time since I've done much mechanic work other than general maintenance and was always confused about the vacuum systems on engines anyways.

Thanks for any info or suggestions.
Posted By: GrantCee

Re: Carb and vacuum issues - 03/23/19 06:30 PM

The carb most people use is the 32/36 DGEV. It is not quite bolt-on, though; you'll need adaptor plates that go between the manifold and the carb, for starters, and the carb has to be jetted for the 2.6l engine.

The easiest thing to do is buy the Redline K610 conversion kit, which comes with the carb pre-jetted and all the parts to do a proper conversion on a Montero.

Once installed, you can delete ALL of the vacuum lines EXCEPT the one from the carb to the distributor (vacuum advance). All of the vacuum ports on the intake manifold will need to be capped off as well.
Posted By: Tuxedo_Ranch

Re: Carb and vacuum issues - 03/25/19 07:49 PM

Thanks for the info GrantCee!!!

Thanks to the service manual downloaded from "mitsubishilinks.com", I spent the weekend going through the vacuum system. Since we don't have emissions standards in Kansas, I removed the "High Altitude" system and found about a dozen lines that weren't routed or attached properly. Had to bypass the "Thermo Valve", because it had two broken nipples. Doesn't the "Thermo Valve" only control the choke or am I wrong?

It seems to run a lot better now. But I still want to get the Weber you recommended, so I can get rid of all the vacuum lines rats nest, just gotta get mama to agree. I'm only getting about 7-9 miles per gallon, so it won't take long to pay off the Weber if it will double the mileage. What do you think I'll get for mileage with the Weber??
Posted By: GrantCee

Re: Carb and vacuum issues - 03/27/19 12:26 AM

Originally Posted by Tuxedo_Ranch
I'm only getting about 7-9 miles per gallon, so it won't take long to pay off the Weber if it will double the mileage. What do you think I'll get for mileage with the Weber??

When I put mine on and tuned it properly, I was getting 24-25 (however, I'm not running huge tires — 30.5", one size up from stock.) That was with the original Jet valve head, and of course everything else was dialed in correctly.

I've since replaced the original head with a plain 2-valve style, and I'm getting 20-21 (the Jet valves allowed the engine to run much leaner for better emissions, which also meant better fuel economy.)
Posted By: Tuxedo_Ranch

Re: Carb and vacuum issues - 03/27/19 04:44 PM


Thanks again for the responses. Being a newby is tough, not just new to this forum but this is the first forum I've ever joined. When I was reading threads, as an outsider, I realized what a great group of people were members. The group seems to be very friendly, are very knowledgeable and always willing to help out. I don't know of anyone else in Kansas that even owns a Mitsubishi or a Raider, they're just not that common. My Raider will be mostly so I can run around with people out here that run around on their side by sides (I can't afford a $20k toy). figured I could get the Raider up to speed for around $5-10k through about 3 years, still be able to use it on the ranch and drive it down state/federal highways if I want.

That's really good mileage, difference should pay for the Weber carb in less than 10 tanks of fuel. I'm running stock wheels and tires for now but have some 30.5x11.5 R15 Super Swampers on 15x8 ProComp alum wheels ordered (the wheels were only $62 each). I still have the original Jet Valve Head and don't plan to change it.

I've got the stock Mikuni running halfway descent, finally, but it is dumping way to much fuel (as mileage shows) and is running so rich the tailpipe is BLACK and you can smell unburnt fuel even when it's not running. Plan to do some more research to try and figure out how to lean it out. I've done a lot of dirt bike complete rebuilds from the floor up, so I understand engines and am comfortable turning wrenches, but I don't have as good an understanding about 4-strokes.

I need to take some pictures as I make changes to my rig. It is starting out really plain and kind of rough but have been doing lots of research and have big plans for it. Should be getting my OME suspension lift this week. Also ordered a 2" body lift from 4crawler.com, some fender extensions from ebay and lots of parts from rockauto. I have a general 3 year plan for upgrading; 1st year is to get it running descent and driving good (lift kits, complete front end rebuild, upgraded wheels/tires and anything else MaMa will allow. 2nd year is the body work (rust repair, bob the rear top off, roll bar, fast back top, rhino line inside, paint outside gray, lights all around, after market bumpers and a 12k winch). 3rd year will be a complete drive train replacement (4M40 diesel, tranny, t-case, newer model diffs w/ lockers and at least 33" tires). I'm also thinking about building a complete cage for it at some time.

Sorry for running on, but as you can tell, I'm really excited about this project. I'm 53 years old and this is the first time I've had a chance to take something like this on (makes me feel like a kid again).

Posted By: rxinhed

Re: Carb and vacuum issues - 04/07/19 01:26 AM

[Linked Image]


I'm a sophomore to your senior. However, I'm not new to Mitsus. It sounds like your plan is eminently achievable. I'm going on 8 years with Pearl, above, and using the combined resources of the core Wire guys and AZ Crew to achieve my goals.

We look forward to your photo documentation and progress.

Montero ranch
Posted By: Tuxedo_Ranch

Re: Carb and vacuum issues - 04/08/19 03:29 PM

GrantCee and rxinhed,

Please follow my post about my re-build in my new thread "87 Gen1 rebuild in Kansas"

I appreciate your help and responses with this thread, but I feel it is getting off topic, so I thought I'd better start a new one.

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