Put my 73 through a few more paces and little tests today......

have a bog when I give it too much gas, and a backfire through the exhaust at high RPM's....

Im thinking of backing off the timing a little, cant time it properly (no marks on balancer) good idea? any other input?

 

Put your own mark on the damper. Find TDC on number 1 cylinder and mark the damper for "zero" (doest mater if the cylinder is on the compression stroke as the TDC isthe same). Then use a timing light with the retard function to set initial at 8 degrees. PS, are you sure there are no marks? I've only ever seen one with out them. Maybe you just need to clean the damper. BTW, You will destroy your engine if you guess at timing.

 

I suppose that would be an easy enough solution, thanks, my light is capable of that, it never crossed my mind.

Im not sure how guessing at timing would "destroy" an engine, that would have to be a pretty brutal guess and run like that for a while????

thanks for your help, what I was really after was whether or not this sounds like a timing issue, or if the two issues (backfire and bog) could be related to 2 different things, (such as timing and Accelerator pump Rod position on the carb for example)

thanks again for your thoughts

 

Like Bear said, is your balance dirty? Mine was so bad I didnt think it had marks either. I cleaned mine by getting under the truck while the motor was at idle, and safely used my drill with wire wheel to grind away the accululated rust and funkas the balancer was rotating... Presto... But as I found out in a previous post, my balancer was bad, (the outer ring had slipped, so its refernce marks were not in line with the true crank position) so I still had a crazy time getting the timing set.. no pun intended. Barca

 

Until the timing is right, there is really no way to know if it is a problem. Yes, timing could cause either or both of your problems, but it doesn't mean it is. Try what Barca said and then verify the marks if they are there, if not make you own. If I had to quess, I would say that your timing is already retarded, causing both problems, but that's just a guess and don't take it as fact.

As to the timing destroying your engine; too retarded and you can get excess fuel washing the oil off the cylinder walls, not good for the pistons, rings and cylinder walls. Can also cause exhaust valve problems. To advanced and it will eventually knock a hole it a piston, even with only light pinging.

 

No, the timing marks are there, but the balancer has slipped, it reads about 42 degrees BTDC at idle

thanks for the advice, next time I get a chance Ill go ahead and do that

 

I gave up on the light and timed mine by ear. We did the same thing with Scooter's truck and it runs perfect now. He'd been driving it with a ping for a while and didn't know what the "rattling" sound was. I think my balancer my timing indicator wasn't matched to my balancer or something because when I'd time it with the light it was running like crap.

 

Having been a professional mechanic for a long time, I just used to love guys like you and Scooter. Neither one of you has a clue, of either how little you know about engines and tuning them and if it doesn't blow up how lucky you are it didn't.

 

Yeah, I know. There's been a real epidemic of engines blowing up at the slightest hint of mistiming. Seems dozens of us non-professional mechanics are blowing things up on a daily basis. I count my blessings every day but if you see a mushroom cloud raisng from this side of the state you'll know where it came from.

How many degrees of error do you think an engine could handle before it blew up?

 

Geez....

Thanks for essentially calling my friend a moron, who coincidentally probably just replied to this thread because I started it....how nice of you.

[sarcasm]Im so glad we arent allowed to post tech in the Northwest chapter, because I got such a friendly response here, why geez, I even got Ivan called an idiot!!!!, it must be a NW chapter thing, we all have garbage trucks that are gonna blow up...... [/sarcasm]

I do appreciate your response and help, but dont you think your being a little brazen and rude to a fellow FTE'er?

Played with the timing by ear this morning, didnt have the energy to do Bears idea at 4:30 AM, but wnated to tinker nonetheless because its been bugging me all night, I started by thinking it was too far retarded and an exhaust valve was opening early, so I advanced it and went for a ride at 4:30 in the morning and it ran like CRAP....

backed it off a little, another ride, ran better, but still like crap.....no backfire either time

backed it off more, and idle sounds sweet again, but two neighbors had lights on in their houses that didnt when I started, so no ride, I parked it and came in, dizzy is right back to where Oldhalftons and I timed it to originally (or pretty close)

I turned the lights off in the garage and revved it up good by hand, didnt see any spark jumping wires, so pretty much rule that out....

I know I dont have a stuck valve, because youd hear it all the time all through the RPM range right?

I doubt I have a burnt valve because youd think it would do it ALL the time, and not just sometimes.... and wouldnt I also hear that all through the RPM range?????

Im really starting to think the carb needs to be jetted down a step or two, it is DEFINITELY running rich, it smells rich, and revving at idle gives a nice puff of black smoke..... and it also Bogs and stutters good when you romp on it......

so heres my new theory that I want some input on, Im thinking that excess raw fuel (because its running rich) is getting ignited when it first exits the head by a very hot exhaust valve? thoughts?

Thanks for all the thoughts so far, keep it comin

 

I read my spark plugs shows me timing and jetting as well as a few other things

 

If there are no marks you HAVE to time it by ear, and if you can do it, its not going to blow up. anyone with good test taking skills and $200 can be a "professional Mechanic"


Try leaning out the primaries 0ne or two steps but leave the accell pump alone right now. when you adjust the the accell pump you might want to increase its arm travel.

usually when a carter/edelbrock bogs, its actually needs more of a pump shot.

 

Uh oh Kevin . . . you're gonna give me an excuse to say something mean about your Edelbrock carb. It does sound like you're running way too rich. Is that the new carb on there?

 

its a new carb and I think its a 750. I know its a nam choke and they are set up rich out of the box.

kevin have you gat a vacuum gauge yet? you need a manifold vac reading before you can tune your secondaries right.

 

You guys are all a bunch of idiots. I was asking my uncle who's a double black belt mechanic thrice recognized at the Professional Cultured Mechanics of the World convention, and it's TOTALLY your pipes here. Your pipes arent giving enough backpressure compared to the immense flow of your air cleaner, and you're going to crack a valve seat if you dont put an enormous exhaust tip on there. Keep in mind that a honda needs a 4 inch tip AT LEAST to utilize all of its power, I'd say you need about 3-5 6" tips from a diesel supplier, they usually run better. If you're still backfiring, you may need to run an intercooler mounted underneith your oil pan to draft all the hot air out of your exhaust so it doesnt ignite the unburned fuel, or "backfire." That's the only way your rig is EVER gonna run right.





Sounds like youre runnin rich kev, but I'M not a professional mechanic, in fact you better lean it out cause i work at schucks