8.1 Phosphoric acid / Barnacle Buster rinse

John

The answer might be under our sink in the galley.. Rubbermaid trash can. I think it's 7 gal. They make a 10 gal one. Looks narrow enough to fit. Just wonder if the tube is long enough to reach which I suspect it is....

That's a great idea! If worse comes to worse, maybe I can extend the tube.
 
Hey guys ...is barnacle buster safe for the impellers? I ask because it suggests removing the impellers on their website, but that's for the circulation method which I assume would be a needed step for that to work. Obviously removing impellers on my 8.1's is a job in and of itself, so I'd like to avoid that if at all possible. Plan is to pull 7gals of barnacle buster in through the on board flush system and let sit for a few hours, then flush. (port engine is running hot)
 
I talked to the Barnacle Buster people and they assured me it would not harm the impellers. I flushed both raw water sides almost a year ago and have had no problems.
 
I talked to the Barnacle Buster people and they assured me it would not harm the impellers. I flushed both raw water sides almost a year ago and have had no problems.

Great ...thank you!
 
just a thought, if you are worried about impellers, don't forget all the hoses that attach to everything else. I would be concerned more about them.
 
just a thought, if you are worried about impellers, don't forget all the hoses that attach to everything else. I would be concerned more about them.

Right. Someone mentioned clamping off the hoses to the shaft seals which I had planned. Any other ones I should be concerned about?
 
Hey guys ...is barnacle buster safe for the impellers? I ask because it suggests removing the impellers on their website, but that's for the circulation method which I assume would be a needed step for that to work. Obviously removing impellers on my 8.1's is a job in and of itself, so I'd like to avoid that if at all possible. Plan is to pull 7gals of barnacle buster in through the on board flush system and let sit for a few hours, then flush. (port engine is running hot)

Your 'plan' is exactly what I did on my 8.1s and for the same reason. I think the circulation method would be required if the let it sit method produced no real results. Phosphoric acid is not very aggressive, it's probably akin to strong lime juice or strong vinegar, it is used in some soft drinks to give it tartness. Of course the concentration levels from drinks to Barnacle Buster to Klean-Strip are unknown quantities.
 
Your 'plan' is exactly what I did on my 8.1s and for the same reason. I think the circulation method would be required if the let it sit method produced no real results. Phosphoric acid is not very aggressive, it's probably akin to strong lime juice or strong vinegar, it is used in some soft drinks to give it tartness. Of course the concentration levels from drinks to Barnacle Buster to Klean-Strip are unknown quantities.

Thanks ..yeah I’m looking forward to doing this in the next couple of weeks. Right now water pressure is anywhere from 30-50% less on port vs starboard, and port temp is 9 degrees warmer running at 3500 rpm. (Took temp at manifolds to confirm). I’ll be sure to follow up with results in this thread. Fingers crossed!
 
Alright guys ...another question. I'm planning on heading down to the boat to do this over the weekend here. I'm going to do the suck up 10 gallons or so of this stuff and let sit for 6-8 hours method, then flush. I read somewhere else that the 8.1 2005 exhaust system drains the water out of the system on shut off ...this being the reason why it always takes a bit for the boat to start 'spitting' out of the sides upon startup as it has to fill up the raw water cooling system with raw water again. Is that true and if that's the case, will sucking barnacle buster in and letting it sit be effective if it's going to drain when I shut down the engine? I can't imagine it would all drain, but the heat exchangers aren't exactly sitting very low, and that's definitely one of the key components I'm targeting for this.
 
I agree - pointless sitting in the sytem as it is not effectively flushing the exchangers. By way of example, pull the inlet of the trasmission exchanger and bugger alll water comes out so 2/3 rds or more of the of the exchanger is not being cleaned. IMO only way to do properly is to circulate the chosen solution or remove altogether and take it to a radiator shop.
 
I did the soak and flush method today ....from what I can tell, really didn't make much difference. Port is still running at 165 at cruise, whereas starboard is 159. Might have helped a little.
 
Another thing to consider, what do your water pressures run? I had an issue and my water pressure was running high along with the temperature. It was finally resolved when I took the heat exchanger ends off and cleaned it out. You can’t always flush an obstruction, sometimes you need to clean it out.
 
Haven't tried it yet but am about to....my thoughts for an 8.1 (please note I was going to flush in the normal direction of flow using Rydlyme)

1. Find suitable size bucket/tub and drop in 360gph or 500gph bilge pump.
2. Remove inlet hoses from trans coolers.
3. Plumb a single hose from bilge pump to vicinity of trans coolers and plump to a t-fitting.
4. Plum the outlet sides of the t-fitting to the inlet of each of the trans coolers.
5. Remove ex manifold hoses from the heat exchanger on each motor and plumb return hoses to each of the outlets of the heat exchangers.
6. Plump heat exchanger return hoses of each motor to a t-fitting.
7. Plump the remaining t-fitting outlet from each motor with the return hoses and route back to to the bucket.
8. Fill with desired solution and circulate in accordance with instructions of the flush solution.

Removing the ex-manifolds from the circulation at step 5 will bypass the problem of the returning the flush solution from the ex-manifolds and will also therefore bypass the shaft seal circulation with feeds from the ex-manifolds. So neither your ex-manifolds nor your shaft seals will be circulated with the flush solution.

Thoughts or potential issues?

Juggernaut, I’m curious if you ever got around to doing it this way? I was looking at my system today, and it seems entering through tranny cooler and exiting from heat exchanger would be the easiest and most worry free way to go. Not having to pull impellers, worry about shaft seals and water intrusion would be ideal, and this method solves all of that. Did you see any downside to bypassing fuel modules and water pumps?
 
Here’s some pics of what I built today after 3 trips to Home Depot. I’ll circulate barnacle buster for 6 hours tommorow. I hope this addresses the high water pressure issue I’m having on starboard side. Please excuse the dirty bilge. I’ll clean it once spring chores like this are done!

5 gallon bucket with a 600gph bilge pump at the bottom. Bilge pump is connected to two hose fittings to step up to the large-ish tranny cooler inlet.

4FD3756C-A188-4B2E-AEC0-5C492162C8E5.jpeg


Inlet point at tranny cooler:

7696C336-E444-43B9-85D6-59475B861D05.jpeg


This is one of the outlet hoses from the heat exchanger which attaches to the manifold. I pulled it off the manifold and fitted another hose here. Same on the other side.

3E50450B-1841-43D4-A611-3B0A6D8D2E93.jpeg


The two hoses from the heat exchanger come to this T fitting which converge to one hose that leads back to the bucket.

7FFC10F1-3112-46A3-B5CF-7127D64373D0.jpeg


Fingers crossed
 
Used the SeaFlush last fall for first time. Did AC, genny and both motors with the Admirals assistance. Took 90 min start to finish. I secured snorkel tube to 5 gal bucket by drilling holes in top rim and using wire ties to hold in place. Had second 3 gallon bucket to add antifreeze to 5 gal bucket as level dropped. Pour antifreeze down shower and AC pan drain to do shower sump. Do my fresh water same way as cfd95.
 
Juggernaut, I’m curious if you ever got around to doing it this way? I was looking at my system today, and it seems entering through tranny cooler and exiting from heat exchanger would be the easiest and most worry free way to go. Not having to pull impellers, worry about shaft seals and water intrusion would be ideal, and this method solves all of that. Did you see any downside to bypassing fuel modules and water pumps?

No, I haven't gotten around to doing it. Instead, Ive since replaced the trans coolers, inspected the oil coolers which were spotless and rodded the engine heat exchangers. I've bought the hoses and various fittings as the engine heat exchangers are not perfect and temps can get to around 75 degrees C, compared to a rock solid 71 degrees C when I bought the boat.

Your plumbing setup looks like how I would have done it :)
 
Well that did the trick. Starboard engine water pressure was at 21psi at 3500 rpm ..almost double what port was. It now runs at 9psi ..lower than the port now which runs at 11psi at cruise. Seems all obstruction muck has been cleared. Guess I need to do the port engine now.
 
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