Flushing

[wufibug]

1982 Bayliner replaced Volvo 5.0 with marinized 98 Suburban 5.7 vortec TBI injected. The engine is salt water cooled and I've read that the key to longevity is draining an flushing as well as possible with fresh water after each use.

The lower intake manifold has 2 threaded water outlets, One is obviously for a heater hose [passenger side pic 1], the other probably also a heater hose though it is set up for a flared fitting [driver's side pic 2]. I am not using a thermostat so flushing after each use with a garden hose should not be impeded. Thought I would plug the passenger side and put a shut off valve and hose bib in the drivers side hole to flush the top end.

The mixing manifolds also have to threaded holes. The forward hole is the hose barb for the inlet from the head. The other was plugged. I was thinking of replacing the aft plug with a drain to make sure no water sits in the manifold and possibly gets into the head.

Is my concern for salt water corrosion creating more problems than I solve?

PS: tried uploading the pictures, but even compressed they are too large. What's the secret?

 

[Horigan]

You might want to consider installing a Neutra Salt system instead.

 

[bruceb58]

I am not using a thermostat so flushing after each use with a garden hose should not be impeded.

Why would you not want to use a thermostat?

 

[Scott Danforth]

I'm with Bruce, why are you not running a thermostat. not using a thermostat is counter intuitive and causes more problems. you would need to add a restricter plate to slow the water thru the block so it actually can pick up heat, and if the motor is not brought up to a minimum of 150 degrees, the wear on the motor is severe

Also hope your not running the Automotive (truck) TBI setup. that is not Marine rated.....as in BOOM

Horigan has the VP solution posted above. either that or simply run on muffs when you get home

 

[ericga]

Perko makes thru-hull flush kits. They use a check-valve system activated by water pressure. You may want to look into that. The installation of a Neutra-Salt system is easy and straightforward. Note that a TBI will run really rich without a thermostat.

You need to downsize your picture and/or save it in a more efficient format (jpeg, gif etc..). The easiest way to accomplish this is to open the picture, use the snipping tool and save your snip in jpg.

 

[wufibug]

I really appreciate the comments.
1. I will reconsider the thermostat.

2. I like the Neutra salt idea, though a bit pricey at $300 + solution. I am not a chemist but I can accept that it will neutralize the salt in seawater. I am, however, a little dubious about the claim that it leaves an anti-corrosion coating on the metal parts is contacts. Am therefore also looking at the Superflush SF-400C fresh water flush system which is only $80.

3. Scott, I am unsure as to why you think using the automotive TBI spider injector system is dangerous. It is a totally sealed system in which fuel is injected directly into the intake runners. Even if there were excess pressure, that fuel overflow is confined to the lower intake and inhaled by the engine. I am curious as to how a marine TBI system differs. I guess it could have a spark arrestor on the throttle body, but since that device only meters air and does not mix fuel and air like a carb, it seems unnecessary.

4. Eric, thanks for the advice on uploading. I tried compressing the original picture file which reduced it considerably, but not enough.

 

[Scott Danforth]

I have used both the SF-400 and the Neutra-salt system. the SF will eventually start to leak and the neutra salt costs money each and every shot.

I also know the inventor of both systems.

the marine EFI system is designed from ground up to SAE 1171 standard. the Automotive system is not. the ECM on the automotive system is also non compliant.

are you at least using a marine EFI pump assembly?

 

[bruceb58]

Out of curiosity, what ECM are you using? Hopefully, not the stock ECM that came with the truck.

Distributor?

Fuel pump?

 

[wufibug]

1. I believe the truck ECM would have to be reprogrammed for the marine application. GM puts the circuit boards in a sealed aluminum finned housing.
2. The stock distributor is a fully sealed unit.
3. I will use a marine high output [80psi] pump [still looking for one] and external pressure regulator.

 

[bruceb58]

If you are using the stock ignition, the spark advance characteristics are completely different that what you need for a marine application.

If you are currently using the stock program for the ECM, it is in open loop mode since you aren't using 02 sensors. Just the fact that you aren't running a thermostat means its running open loop. Eben if you were running a marine temp thermostat, your fuel tables are all wrong since its based on a much higher temp which is too high for raw water cooling.

You have a Costco sized can of worms on your hand.

My suggestion...pull off all the EFI stuff and put on a carb and a marine Delco distributor.

 

[wufibug]

As I understand it, reprogramming the ECM is something that is done pretty commonly for a variety of applications. The ECM re-programmer felt he could compensate for the absence of O2 sensors, the removal of EVAP, EGR & PCV systems, and the different power curve normally encountered in marine applications. Whether he is right remains to be seen.
1. Thanks to the comments of this forum I am going to run a 160 degree marine thermostat.
2. I have already gone so far down the road with the spide rfuel injection that I am reluctant to abandon it without a try at least. If there are problems that appear insurmountable. I will have to invest the big bucks in a marine carb/intake system.
3. As I understand it, fuel tank pressure is relieved in two ways. First through a relief hose/valvesetup from the tank overboard. I haven't tracked that line yet nor where it exits the hull. If anyone knows where Bayliner put that, I'd appreciate the heads up. Second through the EVAP system. Far as I know boat engines did not come with EVAP as the charcoal canister with trapped heptane would not have been safe. There is a debate about whether the overboard pressure relief valve is adequate to allow rapid fueling. Some folks say they've removed the EVAP from their cars and just put a hole in the filler cap. Others say that did not resolve the problem. I've seen some improved marine check valves that should help if there is problem with excess pressure.
4. I don't think the stock vortec distributor needs to be modified. It is sealed and electronicallyl controlled. It uses the same external coil as the Volvo Penta [GM 305] did. Comparing the old Volvo Penta distributor with a standard 305 showed that the only difference was the advance mechanism was changedso the housing could be sealed. Again that is already the case with the stock vortec unit, which BTW, is a much simpler and nicer setup.
4. The remaining two issues are:
a) Finding the right fuel pump. External 80 psi
b) Modifying the thermostat housing designed to distribute water from the head to radiator so it delivers water in two directions to both manifolds. I am assuming there is some reason to have this distribution split off from a single point so that the same amount of water goes to each manifold.

 

[bruceb58]

There are no lines back to the tank from the fuel system in a marine application like the automotive system uses. You can not do that either. It is not safe.

The distributor between the engine you have in there vs the Delco Voyager is completely different. The marine coil and distributor each have 2 connectors on them. I am guessing yours doesn't right?

As far as the thermostat housing is concerned, you have a Volvo thermostat housing on there right?

You have pictures of how the cooling hoses are routed?