Took my GPA for a Swim

[Donovan]

Everyone,

I had to see how it went in the water and took it to a local lake to try her out and see if I had any major leaks. After 7 years and numerous mistakes she swam:



I made a number of mistakes starting out in the water by trying to "swim" in 1st gear...that was getting me no where fast!!! I then tried 2nd and she performed great!!! The only thing is that I kept coming out of the water in 2nd and dogging the vehicle on the steep ramp. After 4 in and outs I finally figured out that it had to come out in 4WD low and no problems.






The one thing that surprised me is that the bow went slightly underwater bringing a little water on the deck before she rose and that was not going in very fast. Not enough water in the forward compartment to require the bilge pump but a little unsettling as the driver.

I did not stay in too long as I had no back up electric bilge pump if the engine failed and did not want to sink her on the first outing. I never had to use the bilge pump (never enough water) and everything performed flawlessly. Now to complete the finishing touches and I will do a long swim in the future.

Donovan.

[bobskinner]

Well done! Got there at last, there is nothing to compare with putting your amphib in the water for the first time after years of work (with one obvious exception), I remember the joy of swimming my DUKW after a long rebuild, making sure the welder was aboard at the time, if it was going down I wanted him on it as well. I will give a few tips here for new Amphib drivers:- When entering the water, drive in with the prop out, then as soon as the vehicle is floating engage the marine drive, put the transfer case into neutral and away you go. At every amphib event I see vehicles driving into the water with the prop turning and I always think 'best keep clear of them on the water!' Another tip I had from a military DUKW driver is, as you exit the water put your hand on the marine drive lever with just a little forward pressure, as the prop clears the water it will slip gently out of drive, this certainly works for DUKWs and GPAs, don't know about Amphicars though. And finally, before driving ashore ALWAYS engage front wheel drive with low speed in the transfer case and 1st gear in the transmission, sometimes they will come out in a higher gear, but will always come out in first. The last thing you want to do is stall on the exit, especially if there are vehicles behind you and a huge crowd watching, which there usually is. Anyway, now you have finished the hard work you can look forward to years of fun on the water.
Best wishes
Bob Skinner

[bobassel]

My Compliments Michael !
All those blood, sweat & tears are not in vain
I hope you will enjoy your GPA as much as I do!
Bob

[Donovan]

Bob S.,

You are so correct. Luckily I had very few people watching and it allowed me to learn how my GPA went into and out of the water.

Bob A.,

Thank you for all your help over the years. One day I hope to make it to one of you amphib meetings that look fantastic! Definitely something to try and do however I doubt that I would bring my GPA!!

Thanks again and if you are ever here, a swim can be arranged.

Donovan.

[GPA2196]

Bob S,

Thanks for the advice. I've been driving swimming my GPA for a few years now. What is your rationale for engaging the prop in that manner? I understand about not running it when dry (lubrication from the water on the packing seal) I find if I engaged after going in, the forward momentum will spin the prop and cause grinding when engaging the PTO. In fact page 18 of the GPA operators manual clearly states that the operator engage the prop as step (3)(a)(4) and the next step (4) is enter water. Additionally, movies of DUKW's entering the surf clearly show the props spinning prior to water entry. I usually engage a few feet from the water on the ramp when the prop is stationary and not spinning from water resistance. Obviously I make sure nobody is behind or under me. I was just curious about your statements, also I have never experience the popping out of gear you describe, I've probably got well over one hundred launches and landings of experience.

Thanks,
Tony

[bobskinner]

Hello Tony,
Firstly I must say that most of my amphib experience is with a DUKW (25 Years), however I think most of what I learnt ( much of it the hard way) also applies to the GPA. Regarding entering the water with the prop out, it was Jack Tomlin, a man with many years of experience with DUKWs who told me not to drive in with the prop turning. He explained (as to a small child) that as you enter the water and the bow rises the stern dips down and if there are rocks unseen under the water they can contact the prop with resulting damage. I agree that if you know well the point where you are going in the risk is negligible but most times I have'nt a clue what is under the water, one of my rules is let someone else go in first and then follow them if they get afloat without problems. I think it is good to keep to a routine and I always go in with the prop out and engage the drive when afloat. I always drive in slowly, I have seen people drive in at full speed to impress the public and tear the sealing bellows off the drive shaft tube, amazing how much water gets in then! Regarding the movies of DUKWs entering surf with the props turning, that is a bit different, going into surf you need water drive straight away. Also don't forget that all these movies were made of vehicles in service and if the driver caused damage good old Uncle Sam or the British taxpayer picked up the tab and supplied the replacement parts! Perhaps you have misunderstood the slipping out of gear I described, what I meant is that it is not neccessary to stop the vehicle when landing to take the prop out of drive. There is nothing more annoying than coming out of the water and seeing the vehicle in front stopping and playing about with shift levers, my rule is, get out and get out of the way of those behind, slipping the prop out of drive on exit makes this easier. Sorry if this is all a bit long winded, we all have different ways of doing things but I have found by experience that these methods suit me best and reduce the risk of problems for myself and others.
All the best
Bob

[GPA2196]

Bob,

Thanks for your detailed response. Yes I usually enter from concrete boating ramps so haven't really had the concern of unknown underwater obstructions. Plus I usually enter fairly slowly. I have done the occasional splash into the water, as you know the GPA doesn't have the front drive tunnel as the DUKW does. The GPA does have the drag link seal there which is pretty substantial and bolted not clamped, but I can see how that could be stressful on that old rubber. There is also the vulnerable seal on the front of the transfer case where high pressure water could potentially enter. I agree, everyone has their own style dictated by where and how they use their vehicles. I was more curious about the reasons and your comments about "staying away" from those who go in the water with their prop spinning. I've always considered myself safe on the water and have participated with other amphibs with no issues. I had fun at the Evansville convention with David Welch and his DUKW on the Ohio river swim which I believe was close to a 10 mile swim.

Cheers,
Tony