Re: Mercruiser 320 EFIs
 

Cuda's Minx was a yachet tender in it's previous life.. Low hours, but may not have been maintained well as far as flushing goes.

Engine ran strong before the meltdown, I would bet they would run real well in your boat. I'm not familiar with the injection issues Cuda mentioned, but it seems to me if they are overfueling it would be fixable with some injector tweaking..??

Re: Mercruiser 320 EFIs
 

24*- nice set up, If they are running well let em' rip. I had one that ran awsome 5500 rpm all day long, and one that would lean out and blow up :( when pushed hard. I loved the look and the fuel efficiency of them and I may even go back to them with a modern ECU (true MPI) not batch fire like they are stock. The injection parts are not a Mercury specific item. heres a little secret....injectors are from Porsche 928. I have a guy here in CT that ran all the part #'s and can get anything you need. The TPS is no longer available so we are working on some sort of spacer/adaptor to mount on the end of the throttle shaft. Let me know if I can help you out, I have a bunch of info I've collected over the past 5 years.

Re: Mercruiser 320 EFIs
 

I forgot to thank Cuda for hooking me up with those parts. I've also been thinking about the supposed design flaw washing the rings, I'm thinking the batch fire may have had something to do with this, since the injectors fire when the valves are closed. I'm thinking the fuel would drop out of suspention and puddle at the valve ?

Re: Mercruiser 320 EFIs
 

Thanks guys.....

Batch fire......? I've never heard that term. Funny about those injectors. I own and operate a Porsche repair shop in Minneapolis and I noticed that the fuel pumps in the boat are the same as in my '78 911......:)

Now I just need to get educated on Chevy/Mercruiser stuff. Is it true these are 4 bolt main blocks?

I was thinking I could update to the MPI set up some day.....sounds like big money?.....might be worth it though.

Sonic......when you say running hard what does that mean? How long can I run this wide open?......It does seem to turn 5500 rpm also.

BTW: I'm running it on Lake Minnetonka just outside of Minneapolis, Minnesota.

Thanks,
Aaron

Re: Mercruiser 320 EFIs
 

I was also thinking maybe the problems were with the 1987 models?.........so maybe my 1989 versions are "sorted".

Re: Mercruiser 320 EFIs
 

Yes, the definetely are four bolt. I rebuilt that block.

Re: Mercruiser 320 EFIs
 

Possibly corrected.All the ones we sold were 87 models.And all were 4 bolt mains.

Re: Mercruiser 320 EFIs
 

I had sold a couple of Checkmates back in the day, that had these motors w/Alpha SS drives. They ran real well....however, even at the time(early '90's), they had a reputation for electrical gremlins in the computer, and oil consumption. I remember that they were an adaptation of the short-lived Crossfire injection that was used on some Vettes around the same time. I recall a particular 21 Checkmate that would run 70+mph w/the 320/Apha SS pkg. if you had the stones to hold on.
Hugh

Re: Mercruiser 320 EFIs
 

Wow I've been admiring your boat and now I see you are right here in MN. FORGET tonka and get that boat on the river. Either the Croix or the Mississippi.

Re: Mercruiser 320 EFIs
 

A few points of interest.

First, the throttle body/ plemum are around, I know where 2 are. The injectors, regulator and the like are bosch off the shelf parts.
The ECU can be replicated by Repair in Fla.

As for the engines, they run very very well, they only have issues when people that fool with them have no idea what they are playing with.
This is the same induction system that is on the merc Hi-per outbaord motors, the 2.4 and 2.5 series.
When it was mentioned that the injectors are fired in batched pairs what is ment is that two injectors are fired at the same time. This is not an uncommon thing with EFI. The best systems run sequential fuel injection, each injector fires on it's own.
I know of a lot of 320 EFI's that still are around and still run very strong. Hell the alpha SS drive that it came with it VERY saught after.
Setup Setup Setup, and they work great once correct.

RT