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What bump?
Posted: Sat Apr 19, 2008 5:38 am
by Rick Westlake
Marykate "Liquid Rollers" spray-on bunk lube works for my

.
Posted: Sat Apr 19, 2008 7:02 am
by Scott
Notice the dreaded void between the bow and the v-block.
I have towed my boat quite a few miles in the 8 years Ive owned it. The ramp at our lake is very steep and you CANNOT get the boat to bunk forward into the v- block.
I tried the "Mac-bump" one time and had all 4 corners of the "Tow Monster" barking. The only thing I succeeded in doing was striping the road.
Granted my trailer is a dual axle and perhaps tows better than a single but the first 3 years we owned the boat it was still a single. I towed the boat every mile I pulled it with about an 8 inch gap.
I pose the question, "does 6 or 8 inches on the trailer location really make a discernable difference? In my mind the answer would have to be , no. Im sure the engineers on the site will educate me as to the reason my thinking is flawed.
For newer board members, I love flogging the engineers, (we have a few) because what fun is knowing an engineer if you cant beat on him every now and again?
Posted: Wed May 14, 2008 5:58 pm
by dennisneal
It REALLY helps if you can find a location where you are going downhill, (even slightly), when you do the "Macgregor Bump"!
Posted: Wed May 14, 2008 7:20 pm
by Phillip
I got one here with a 60hp on the back.
Have learnt, when it stops short of the V (while still in the water) I just open the throttle and in to place it goes.
Just need someone to tell me "when it's in"
Another trick I have learnt....when it is tucked up in the V, I have a chain to duplicate the winch strap. That stops it from moving back.
Also learnt, on my ramp, put your trailer well in the water. Not that you get your tow vehicle wet or anything.
Cheers
Phillip
MAC BUMP
Posted: Mon May 19, 2008 8:37 am
by puggsy
I do not trailer that often, but when I do, and while SEAHORSE is afloat obove the trailer, I float her on right up to the "V" and then connect the bow ring to the trailer with and adjustable turnbuckle...It gets an exact distance...Chain cannot achieve this...there is always some slack,
So when she comes out of the water, she can't go nowhere...stays in the V. No bump necessary. When she is out, i add chain for extra security.
puggsy 06

Posted: Fri May 23, 2008 10:41 am
by Paulieb
How about we just modify the trailer to make the V adjustable and move it back to meet the bow and then tighten it up and be done with it. I to have had trouble with the Mac bump, the anti-lock brakes on my truck do not allow me to brake hard enough. So I just live with the gap and make sure the boat is secured down with straps.
Mac Bump
Posted: Fri May 23, 2008 1:25 pm
by Newell
Just read this thread and can't believe how much work and wear and tear that others have experienced.
Solution for me: Removed the winch turned it over and mounted it on backside of original location. Drilled a hole and led rope (cable or strap) through to hook. Now winch is pulling up not down on the boat. Has worked for 10 years no mac-bump bs. Cost, I think I bought a drill bit.
Just did this mod on a friend's D, also worked for him. Come on now this isn't rocket science and don't give me the credit, I copied another guy.
Newell
Fast Sunday 96X

Posted: Mon Jun 23, 2008 5:07 am
by Nick
I had the opposite problem at the last retrieval. As per normal I did the Mac bump to fully engage the rubber V block. I only moved the car a couple of metres before applying the brakes and the boat slid so far forward it rose off the V bunks by a good 4 inches as the tapered bow slid up the rubber block. I then had to do a reverse Mac bump and then used the winch to bring the boat forward in a more controlled manner. I didn't have any problems using the winch and I think I might utilise more in the future even during the initial placement of the boat on the trailer rather than gunning the motor for those last few feet.
Cheers Nick
Posted: Mon Jun 23, 2008 1:25 pm
by David Mellon
I always have success using the bump. Things to be sure of:
-Empty ballast
-No tailgaters
-Dry pavement
-More than 5 and less than 10 MpH
-Rig should be in a straight line, do not attempt during a turn
-Lock the brakes
-Tighten the strap right away
I have been told that jumping out a few times and tightening the winch as you pull the boat up the ramp will nest it into the bow chock. I have tried that a few times with zero success.
I was unfortunate enough to get a trailer with no bow guides and ended up with hull damage. I returned to the factory for a patch job and bow guide installation. If they give you a trailer without this critical feature get it added. My damage was minor but yours might not be.

Posted: Mon Jun 23, 2008 4:10 pm
by Boblee
David
That scratch is the twin of mine, I had temporarily made up a guide but my son in law smashed it off with his ute rack and the scratch occured when overunning the roller while driving the boat up on the trailer in strong winds.

Posted: Mon Jun 23, 2008 4:19 pm
by Scott
It REALLY helps if you can find a location where you are going downhill, (even slightly), when you do the "Macgregor Bump"!
I did it on a very steep downhill to no avail.
Those scratches are testament as to why you should walk your boat onto he trailer whenever possible. That and powering on is illegal at most ramps.
Re: A liitle Feedback with respect to the MAC Bump
Posted: Mon Jul 14, 2008 7:38 pm
by Stephen Mooney

I too have overdone the bump - bending my trailer ladder. Because of a very steep ramp I ended up with a gap of about 2'. So to overcome this I fixed teflon skids on top of the carpet, once the boat was out I could simply winch it the rest of the way. Not sure if I would transport it very far - I parked it at the ramp on a permanent basis.
Re: A liitle Feedback with respect to the MAC Bump
Posted: Mon Jul 21, 2008 1:25 pm
by pokerrick1
Anyone who can't perform the MacBump on an M is a sissy

IMHO
Rick

Re:
Posted: Mon Jul 21, 2008 1:57 pm
by hart
Scott wrote:powering on is illegal at most ramps.
At my local ramp it's the norm. Actually, I've never seen anybody but me walk a boat on. Out of curiosity why is it illegal?
Re: A liitle Feedback with respect to the MAC Bump
Posted: Mon Jul 21, 2008 5:24 pm
by Love MACs
There is a thread somewhere on this....but basically it is because big boats with big motors, undercut the foundation of the ramp by blowing back dirt, mud, gavel, sand ect causing a hole at the end of the ramp, which can lead the collapse of the end of the ramp. It also causes a hump of said deposits making it more difficult for other to access the ramp.
Allan