'78 OMC 140 TBI Conversion

[Red0ktober]

Re: '78 OMC 140 TBI Conversion

you asked for thoughts, Bondo gave you his thoughts.
You should have specified, "only post a reply if you think like I do" in your original post if you don't want voices of experience.
Often, experience = pessimism around boats. especially when 400 stringers are involved.

I heard him the first time. Saying my 400 is crap doesn't magically provide me with a better boat. Telling me that a non-running carb engine is better than a running TBI conversion is just silly. Saying I'll have a $500 boat with a $1500 injection system also doesn't make sense. I have a $0 boat, and if I invest $300 into the injection system (I have most of the parts on-hand already), then I have a $500 boat that cost me $300. Sounds like I'm $200 ahead.

I get that my boat isn't great. But it's what I have and I believe it's still serviceable. Performance gains would be nice, but I've never had it running properly in stock form so I wouldn't know the difference. While I'd get to use the boat as I desired, it was actually given to my brother and he is the boater and fisherman of the family, I'm the mechanic. My purpose here is to make it so that he can turn the key and have the engine start, which I will do, probably by way of fuel injection.

 

[Howard Sterndrive]

Re: '78 OMC 140 TBI Conversion

in other words: "only post a reply if you think like I do"

to ask for thoughts, advice and ideas, and then insult those biting your bait, is called trolling, and not the kind of trolling people like to participate in here at iboats.

 

[QC]

Re: '78 OMC 140 TBI Conversion

Let's all take a chill pill . . .

There are always strong opinions here about Stringers

There are always strong opinions here about pumping money into Stringers

There are always strong opinions here about potentially non-Marine approved mods

There are always opposing opinions to any of them

Carry on . . . nicely . . .

 

[Red0ktober]

Re: '78 OMC 140 TBI Conversion

My comment was to point out the unproductive negativity.

I have acknowledged that I am not working with the ideal platform, but I will stand behind the safety and practicality of the TBI injection system as I intend to install it. I have not installed it yet, so if you have constructive input on how to install it properly and best meet regulations, I'm all ears. Those who do not think this is a worthwhile investment of my time and money or are concerned for my health and safety are welcome to say so, but doing so rudely and repeatedly is what I consider trolling or flaming. I have started one thread here for this one discussion, it was not intended to be flame-bait.

Can we move on?

 

[Red0ktober]

Re: '78 OMC 140 TBI Conversion

Addressing the fuel return issue, I could simply use a returnless marine fuel pump such as this:
http://www.summitracing.com/parts/HLY-712-801-1

But for uninterrupted flow of fuel, I think a dual-pump with surge tank arrangement would be best. My tank is long and I assume un-baffled.

 

[Jason89sunbird]

Re: '78 OMC 140 TBI Conversion

This is a fun post lol. Bruce the chart you posted gave all the centrifugal advances for 2.3, 3.0, 4.3, 5.7. Only the graph was 5.7. The true advantage of electronic is dwell based on rpm, almost 3 times more spark energy less to wear out!! Sorry it's better and if you upgraded your 454 you would love it and so would the pocket book for gas if you use your boat often enough

 

[bruceb58]

Re: '78 OMC 140 TBI Conversion

Bruce the chart you posted gave all the centrifugal advances for 2.3, 3.0, 4.3, 5.7. Only the graph was 5.7. The true advantage of electronic is dwell based on rpm, almost 3 times more spark energy less to wear out!! Sorry it's better and if you upgraded your 454 you would love it and so would the pocket book for gas if you use your boat often enough

I know the chart mentioned the 2.3 and I didn't post the graph for the 3.0. The numbers in that OMC chart(points distributor) don't jive with the Volvo manual's chart(Delco EST distributor).

My 454 has electronic ignition which was standard from Volvo.

 

[Jason89sunbird]

Re: '78 OMC 140 TBI Conversion

Bruce it's funny how you said it mentioned the 2.3 and didn't post the graph for the 3.0. both statements are right but it's beating around the bush.... You remind me of my coworker, he is older then me and also an ASE master tech. I'm the last word, ie shop foreman. granted it's a 3 man shop... He is an awesome exhaust and chassis tech but he can't be wrong and wants to voice his opinion when it isn't needed like many who have chimed in on this thread... Whats wrong with saying "make sure you have no fuel leaks and the stinger is hard to find parts if it breaks, I wouldn't venture down that road, good luck". Today I just scraped a clean 1987 GMC 2500 2wd 454 because of a rod knock.. I paid 200 for it and scraped it for 400, I told him to call around to see what he could get before he sold it to me.. It wasn't worth it to me to fix it for my labor and parts but it would have been worth it to many others.. I wouldn't have bashed anyone else if they wanted to put their sweat into fixing it, unlike this forum!!!!!

 

[Jason89sunbird]

Re: '78 OMC 140 TBI Conversion

I also don't think you guys realize how smart Red0ktober has to be to get a 3.4l sfi to run and then turn it into a dis tbi. Red0ktober how did you get around VATS?? I build my own astable multivibrater to clock 50hz.

 

[bruceb58]

Re: '78 OMC 140 TBI Conversion

I didn't post the chart before because we were talking about a 4.3L in the other thread. I am just giving you info at this point that the Volvo lists the EST 3.0 distributor as having total spark advance of 13 degrees. The points version shows 28 degrees total in the OMC manual I have. I meant 3.0 in my previous post. I trust the Volvo manual way more than the OMC in this case because the Volvo 3.0 does use the EST distributor.

As far as the OP is concerned, he asked what people thought and he was told the risks. He obviously didn't like what he heard. I have no doubt he can get it to work...I don't think there is a question about that. Working safely is another story!

If it was my boat, i would just rebuild the carb and run it until the stringer drive dies.

 

[Red0ktober]

Re: '78 OMC 140 TBI Conversion

I also don't think you guys realize how smart Red0ktober has to be to get a 3.4l sfi to run and then turn it into a dis tbi. Red0ktober how did you get around VATS?? I build my own astable multivibrater to clock 50hz.

Well thanks! I looked at VATS diagrams for a bit, but ended up just buying a VATS bypass box on eBay.

I put some fresh gas (with seafoam) in the boat yesterday and a new fuel filter. I primed the filter with fresh gas, but in the process of swapping them I obviously introduced some air in the lines and it still has old gas in the carb. I didn't have much time to work on it last night, was only able to get it to cough and sputter. Either my battery or the starter is weak. it will usually crank the first try, but after several tries, the starter won't operate (relay clicks, but not the solenoid) and I have to give it a rest before trying again. I cleaned the terminals already with no improvement. I do keep a tender on it, but my bro said it was an old-ish battery (marine deep cycle / starting). I need to repo my spare Optima Red from a friend and give that a try, it's very strong.

 

[Jason89sunbird]

Re: '78 OMC 140 TBI Conversion

I created my Vat box in 04.. Darn it, I should have sold vats boxes on ebay lol... To tell you the truth I would rebuild the carb too, my time is to valuable now for EFIing a boat like mine or yours... I just got my boat running properly besides the auto carb, the carb is well vented but I want a bigger and faster boat...

 

[Red0ktober]

Re: '78 OMC 140 TBI Conversion

I just ordered a carb kit, so we'll see how that goes. I've never properly rebuilt a carb before, just fiddled with them on motorcycles. I have a dead Isuzu here will all the injection bits except for the right dizzy and the adapter plates, so the cost would be pretty minimal to go to TBI, more a time investment...

The boat could probably become mine if I wanted it. My bro would like it for fishing, but only because it's free. Says he'd rather have an aluminum boat with outboard, if he were to buy one.

 

[U.S.S. Too Tall]

Re: '78 OMC 140 TBI Conversion

Well Red, with you being the mechanic for the family, I think that you will get the carb kit done in no time. I rebuilt the carb on my boat, and I never played with a carb before that. So it was pretty fun for me. Especially getting the linkages back on. I would recommend taking a picture of those before you tear it apart.

 

[Red0ktober]

Re: '78 OMC 140 TBI Conversion

When I say that I'm the mechanic of the family, don't mean professional mechanic, just hobby. Swapped a few engines, done head gasket replacements, clutch, diff, my EFI swap and the like.

I got the boat started again, still the same story. Little rough and won't idle. Ran it long enough to get up to temp and make sure the fuel filter and lines are primed again.

My bro came over yesterday and we talked about it. His expectations are reasonably low. If I can get it to work, great, but he knows it's not an investment.

 

[Red0ktober]

Re: '78 OMC 140 TBI Conversion

It lives! Sort of. [clickie image for short video of the engine running]