lugnut1009

No unfortunately it is totally disassembled at this point because I just knew it was a rod knocking and tore down the bottom end first after removing the engine...

Love my little ratty Nissan 720, it developed a knock and I had it set in my head it was a rod knock. Motor has about 200k, tore it down to find only a head gasket blown making liquid knock. This really ticked me off! Now I have to rebuild the entire engine, the good thing is every bearing and gasket looked good! Nothing was bad except for the head gasket between cylinder 3 and 4 with cylinder 4 looking like it had been steam cleaned. So my question is, if I do bite the bullet and rebuild the engine, how reliable will it be? All my life I've heard horror story's of people blowing money trying to rebuild a toyota or nissan motor and having terrible luck with them. Also, I was going to use the $200 rebuild kits off of ebay. That may not be a good idea but I only paid $500 for the truck in the first place. What are your thoughts and experience with them? If I had plenty of money I'd scrap the 4 banger and put in a V8 with a manual trans and a ford 9" rear end!! But I don't....

Thanks datzenmike!!! That worked great! Back idling again, must have been partially plugged for a while, idles a little high. But I don’t have to use all the pedals stopping at stop signs anymore!! Woohoo!!

If I get a chance this evening I will give this a try datzenmike, thank you for the advice. Makes sense, these are just an overly complicated carb, but not totally different that what I am used to which is small engine carbs on ATV's or Motorcycles. I wanted to remove it and take it apart but was scared all the 32 year old gaskets would crumble and I'd be in way worse shape than I am now. I also plan to remove all the vacuum lines except the vacuum advance and install plugs. I live in Mississippi so no worries about emissions, heck half of my exhaust isn't even there anymore anyway.

1 bolt

Well I replaced a couple questionable vacuum lines with no luck. Then I found a missing vacuum cap, still nothing. Pulled the idle solenoid and it pops open with 12v when the key is on, still no idle. So I gave up and just turned the idle up some, helps but it’s not consistent.

Well I have been putting off working on my lil 720 for a while, just been busy working on other projects. But now I'm being forced to work on it. My primary vehicle (F250 6.0) has the inevitable blown head gasket so I'll be working on it for a while and need to make the 720 reliable. I know I need a drive shaft carrier bearing, need to lift the front and check for slack in the steering joints and box, and now it won't idle! So I think I need to go through all of the vacuum lines and replace them with new hose. Does anybody have a picture or map of the vacuum line routing? Are there any that could be removed or capped off? Or would it be easier to try to find a weber carb and put on it? I am on a tight budget though since my diesel is going to cost me over $2000 in parts alone...

No, manual. It probably is a little wear on every piece. Just need to find the time to clean it all up and get a parts / price list going...

Thanks, the picture looks better than the truck actually does, HA! The interior needs some major work and I still have to do something about the slack in the steering and buy some tires. But she runs great still and I occasionally drive her to work and back.

No clue

Well I did it really cheap hurt to see if it would work, probably not recommended. But all I did was replace the dryer and all the o-rings except the ones on the compressor. I know I should have totally evacuated the system and replaced the oil in the compressor but I didn’t. I just charged it with cheap Walmart r134a refrigerant til it was cooling (didn’t take near what it was supposed to, compressor probably isn’t sealing well). I’m still running it with no problems yet. Now it won’t freeze me out, but it will cool enough that I turn the fan down from time to time.

Well my O-ring kit, dryer, and r12 to r134a conversion kit came in yesterday. I'll start tearing down the system and replacing o-rings when I get time. We'll see how that goes...

Oh ok, guess I never looked for it so I’ve never heard of it.

Thanks Lockleaf! That’s simple. I also plan to break apart every connection and replace the o-rings. Hope the compressor is good. What type of solvent would you recommend? Don’t want to harm the compressor if it is good.

Anybody have a link to what is needed to convert these AC systems over to R134A? I've found the screw on adapters for the fittings, but what else? I plan to also buy a kit to replace all the O-rings in the system and jump out the compressor to make sure it isn't locked up.