lose of power

Ask technical questions about your Ford Bronco II here. Technical write-ups on your axle swaps, engine swaps, chop tops, etc. are encouraged.
rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

lose of power

Postby rayrayd » Fri Jan 02, 2015 9:23 am

Does an 84 B2 4x4 have a second fuel filter besides the one at the carb. I've been told it does by several people but have yet to find it. Anyone know for sure? Mine is spitting and sputtering back thru the carb until it gets warm. Then it idles fine but feels like I'm dragging and anchor. But not all the time. Sometimes it runs fine. Almost sounds like it's missing when it's struggling. Hard to tell with the mudders rolling tho. I've changed the plugs and fuel filter at the carb.

Lance Skene
Posts: 130
Joined: Fri Dec 27, 2013 8:06 am
Location: Calgary Alberta

Re: lose of power

Postby Lance Skene » Sat Jan 03, 2015 8:29 am

Mine only have the one filter at the carb(1 84 and 3 85s), I think the later injected models have a frame mounted filter.

Typically B2s often have electronic issues but the 2.8 has mechanical lifters which can require adjustment to the valve lash which can cause them to run poorly and/or have poor compression, a lose of power is a common result. Normally you will hear some valve noise but if they clatter quite alot they may need to be adjusted. The 2.9 engine has hydrolic lifters so the same does not apply.
'80 Bronco 351M
'85 BII 2.8/Duraspark
'89 F150 302 Supercab

rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

Re: lose of power

Postby rayrayd » Sat Jan 03, 2015 2:49 pm

I changed the plugs yesterday. 4 of the 6 are solid black.

rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

Re: lose of power

Postby rayrayd » Sat Jan 03, 2015 3:08 pm

This B2 has been setting up for 2 years when I got a hold of it. Replaced fuel tank, flushed lines, filter, plugs and wires etc. it's been running ok, smoking a little especially at start, using a bit of oil. I have about 600 miles on it. I'm been wanting to change the valve seals and adjust the valve. Think that is the fix?

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tekatlarge
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Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: lose of power

Postby tekatlarge » Thu Jan 08, 2015 9:25 pm

When you say the plugs were black was that an oil black or fluffy black sooty carbon black?

If the plugs are oily, valve stem seals are probably not going to help you. I have rarely seen valve stem seals really make a change on how much smoking an engine does when it gets tired.

If you want to see how much your engine smokes do this simple test. Find a long hill you can descend without touching the gas. at the bottom of the hill step down on the gas briskly. Look in your rear view mirror, if you have a tired engine your gonna leave a smokescreen like a battleship. It will or should clear somewhat within a block.. If you have bad seals only you won't see a big cloud at the bottom and if there is any it will clear quicker.

Oh yeah the valve noise usually don't adjust away. It is an inherent quirk of the ford 2.9. Has to do with cam and lifters and oiling deficiencies. Just keep the motor Fed, Oiled, and treated well, and you can squeeze a lot more miles out of that lil bugger.
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

Lance Skene
Posts: 130
Joined: Fri Dec 27, 2013 8:06 am
Location: Calgary Alberta

Re: lose of power

Postby Lance Skene » Sat Jan 10, 2015 4:39 am

Tek, he has a 2.8 with mechanical lifters so adjusting them will likely make alot of differance to to how it runs as well as how much noise it makes... although it wont affect oil usage. To improve oil use both the valve guides and seals should be replaced... just the seals wont have much affect.
'80 Bronco 351M
'85 BII 2.8/Duraspark
'89 F150 302 Supercab

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tekatlarge
Posts: 950
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: lose of power

Postby tekatlarge » Sat Jan 10, 2015 10:31 am

Hey there Lance,
I dropped the ball on this one. I failed to see the fact we were talking about the 2.8. I guess my mind was somewhere else.

Yeah a good valve adjustment will do wonders for a 2.8. Also if the plug wires are old a new set a wires helps.

I think I am going back to sleep..
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

Re: lose of power

Postby rayrayd » Sat Jan 10, 2015 10:42 am

Plugs are sooty, not oily. Generally smokes when cranked especially after its cooled off a bit or cold. My cousin is helping me out with getting her going, he is thinking the carb needs to be cleaned or rebuilt. I agree with that with the shape the gas tank was in when I got it. It is the 2.8 motor. We are gonna address the valve seals and adjusting the valves if we can get it running decent again. Thanks for the info guys!

rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

Re: lose of power

Postby rayrayd » Sat Jan 10, 2015 10:46 am

Hey Tek, I will try rolling down the hill and gassing on it and let you know how that turns out. Thanks

Lance Skene
Posts: 130
Joined: Fri Dec 27, 2013 8:06 am
Location: Calgary Alberta

Re: lose of power

Postby Lance Skene » Sat Jan 10, 2015 11:39 am

I wouldnt waste money rebuilding that feedback carb, with a 2.8 you have the option of converting to the duraspark ignition which requires a differant carb all together. The conversion is well worth the effort with better fuel economy and added HP as well.

You need to pull the heads off to change the valve seals so new guides should be done at the same time since they cause most of the excess oil use... the seals alone wont make any noticable improvement for very long.
'80 Bronco 351M
'85 BII 2.8/Duraspark
'89 F150 302 Supercab

rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

Re: lose of power

Postby rayrayd » Sat Jan 10, 2015 9:35 pm

Lance, thanks for the tip, I've read a few articles on the duraspark conversion. I'm gonna look into that. Thanks again, will up date the forum when I know more.

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tekatlarge
Posts: 950
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: lose of power

Postby tekatlarge » Sat Jan 10, 2015 9:41 pm

You can still change the seals with the heads on if you you use the old Indian rope trick.

That is bring the cylinder you are working on up to TDC. Back the crankshaft up 180 degrees remove the spark plug and feed in a copious quantity of say 1/4 " rope into the cylinder through the spark plug hole leaving an end sticking out of course. Now slowly turn the crankshaft back towards TDC until the crank compresses the rope up against the valves. Now you can compress the spring and replaces the seals.

After you re install the seal and spring turn the crankshaft back 90 degrees and remove the rope. Then on to the next.

I have worked on and screwed with feedback carburetors both Ford and Mitsubishi for it seams like forever. I Had a Dodge Ram 50 that had a Jetotronic 2.6 L with feedback carburetor. Of course feedback solenoid failed and truck wouldn't idle below about 2000 rpm or it would quit. I rebuilt the carburetor and replaced a very very expensive Feedback Solenoid. Got it all back together and it ran a lot better and even idled, however driving daily the vehicle was inconsistent. The truck would run great one day and the next it would act like someone was holding on the tailgate dragging their feet. I solved the problem by giving my daughter the truck and in short order she had wrecked it and then ran it with no oil and blew it up. "End of Dodge Ram 50 Problem". It didn't cost me a lot so I let that one slide!

Problem with the early to mid 80s' vehicles using these type of Carburetors is the electronics driving these engines were real crude, subject to radical temp changes and so choked up by emissions requirements they hardly worked and they had to jet everything so lean it is amazing they even ran..

I would highly recommend that any engine that was equipped with the feedback system be re carburetord with a conventional Carburetor. That is unless there is a inexpensive EFI available. I know a guy on another board whom had a Dura-Sparked 2.8 with a regular type 3.8L T-bird v6 throttle body fuel injection. It had it quirks but I think it worked quite well.
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

Lance Skene
Posts: 130
Joined: Fri Dec 27, 2013 8:06 am
Location: Calgary Alberta

Re: lose of power

Postby Lance Skene » Sun Jan 11, 2015 8:44 am

The recommended carb for the conversion is a motocraft 2150, bolts up with no surprises, bonus is you throw out the polution pump and computer along with 90% of the wiring from under the hood. I bought all new parts when I did mine, cost about $600 for everything. You could find everything at a scrap yard probably less than $200.
'80 Bronco 351M
'85 BII 2.8/Duraspark
'89 F150 302 Supercab

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tekatlarge
Posts: 950
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: lose of power

Postby tekatlarge » Sun Jan 11, 2015 6:43 pm

Yep the 2150 is what i would recommend if ya want a simple trouble free carburetor I got a Article on my website that is expressly 2150. it tells ya everything you wanted to know about the 2150.
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

Re: lose of power

Postby rayrayd » Sun Jan 11, 2015 8:31 pm

Man you guys are bomb!!! Thanks for all the great info. I will update the site as the repair progress


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