Hovercraft Cruising Club UK

Open Forums => General => Topic started by: Gary Firth (Gazza) on Aug 25, 2018, 8:01 am

Title: Lift engine.
Post by: Gary Firth (Gazza) on Aug 25, 2018, 8:01 am
Lift engine going in the eagle 4.
Title: Re: Lift engine.
Post by: Nick Flint on Aug 25, 2018, 10:14 am
Have you omitted a video or photo?  :-[

Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 26, 2018, 9:29 am
Pushed the right buttons but no picture.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 26, 2018, 9:30 am
Pic
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 26, 2018, 9:32 am
Removing the dash board with my airbags. (Nothing smutty intended).
Sharpened putty knife and a hammer helped.
Dash has to come out to fit engine. Will be pop riveting it back so itís easier if it ever has to come out.
Will redo the wiring to the instruments whilst itís on the bench (pool table).
Title: Re: Lift engine.
Post by: Nick Flint on Aug 26, 2018, 10:47 am
"EEL level" made me giggle for too long.


Mirth in the Morning.
What ever next ::)
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 26, 2018, 1:35 pm
Lining up for hole in the bulkhead.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 26, 2018, 4:56 pm
More pics.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 26, 2018, 4:58 pm
Another pic
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 26, 2018, 5:20 pm
Just waiting for the 2 part bouancy foam. Then I can continue.
Title: Re: Lift engine.
Post by: Eric Yeoman on Aug 27, 2018, 2:04 am
Hi, Gary,           what can you tell us about the 90* gearbox? Make, weight, cost, etc. Thanks.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 31, 2018, 6:29 am
Go to k and m products. Itís on there.
As for price I have no idea bought as a full kit of parts.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 31, 2018, 6:30 am
More jobs done. Splitter cut out   
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 31, 2018, 6:31 am
Platter hole filled in.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 31, 2018, 6:32 am
Painted to make it neater.

Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 31, 2018, 6:35 am
The foam was a big disappointment.
I was expecting so much more.
I was expecting mt versuvias in a split second of mixing the two parts.
Turns out itís a big disappointment reaction takes an age and the expansion is poor.
(I know how our lass feels now).
Title: Re: Lift engine.
Post by: Gaz on Aug 31, 2018, 6:43 am
You get a better reaction if you warm both parts before mixing, the downside is  the wife gets a little cranky when she finds the tins in her beloved oven. if its pre-heated It foams extremely quickly so you get a bigger foamed volume it also generates a lot of heat
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Aug 31, 2018, 1:46 pm
Iíve done it now but thanks for the tip.
Our lass has come home to engine parts in the oven.
Engine parts in the dishwasher.
I think itís now a surprise if she comes home and thereís food in the oven and pots in the dish washer
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 02, 2018, 5:42 pm
More stuff done
Mounting plate glassed in. This will have rivnuts so the lift gearbox can be bolted down.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 02, 2018, 5:45 pm
Cutting the fan blades using a band saw I just bought for £40 on eBay.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 02, 2018, 7:05 pm
Watch ya fingers.
Finger tips resting on the bed of the saw to stop vibration.
https://youtu.be/kcCStZTS70U (https://youtu.be/kcCStZTS70U)
Title: Re: Lift engine.
Post by: Nick Flint on Sep 03, 2018, 9:24 am
Oh wheres the fun in doing stuff quickly?
As women often say "slow is better".
Thats why they don't do much-----------------


















Discuss.
Title: Re: Lift engine.
Post by: Ronnie L on Sep 03, 2018, 12:17 pm
Most times I find its best to know where the danger zone is.
Making statements such as that ......mmmm......sounds dangerous to me.

Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 04, 2018, 3:00 pm
If you hurt yourself doing the blades. You really need a cork on your fork when you eat.
Safe as houses.


Having the splitter plate removed means my centre rudder was to short and too high. So I had a rummage and found a temporary one.
If anyone has a rudder 300x750 ish for sale please let me know.
It looks odd but it will do
Title: Re: Lift engine.
Post by: Philip on Sep 04, 2018, 6:31 pm
Make one yourself out of foam board. Easy
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 05, 2018, 8:30 pm
Make one yourself out of foam board. Easy


Itís done permatempary.


Jobs stopped until the correct size mounting pillars arrive.
So Iíve rewired the dash all neat and tidy.
Iíve printed a air filter (round box with screw lid resized to suit)
See pics.
Gauze from a anti splatter frying pan mesh cover.
Proper air filter foam from motorbike shop.
I had to drill the holes but it means at least the dashboard moulding will fit.

Title: Re: Lift engine.
Post by: Nick Flint on Sep 08, 2018, 1:06 pm
Rudder looks bang on to my fading eyes. Perhaps a poor colour match tho-- ;)
Title: Re: Lift engine.
Post by: Warby on Sep 08, 2018, 3:53 pm
Looks like rather a large area to the rear of the pivot point (on the larger rudder) and hardly anything forward, which may make the steering "heavy" See "balanced rudders"
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 08, 2018, 4:56 pm
It will perform just like it did before.
Same pivot point.
Would have kept the original if it hadnít have been too high up due to original splitter.
Nick mi old fruit the paint is ordered.
CombiColor red.
Title: Re: Lift engine.
Post by: Nick Flint on Sep 08, 2018, 6:51 pm
I am deeply comforted as I was feeling faint.
Standards man - (Standards).


On a personal note, I feel "balanced rudders"
are often "overbalanced" as I prefer to have
a firm self centering action.
In this way the straight ahead position
is re-affirmed (should this be forgotten) by the driver.












 :-*
Title: Re: Lift engine.
Post by: Jimmy Cooper on Sep 09, 2018, 10:05 am
Balanced rudders.
I am told that 25/75 % is an optimum (using the pivot point as the centre). Checked my Sirocco as didn't like the 'over centre' feel. Felt like it was dropping into turns and you'd have to pull it straight.
The two rudders when checked were 29/71 % on measurements.
I made up sone  SS plates to alter the balance of the rudders by moving the relative pivot point to my give basically the same feel as my Marlin III, 21/79.
Sooooooooo much better.
Now feels good with a more self centering action without be heavy.
Nice when a plan comes together...........
Title: Re: Lift engine.
Post by: Nick Flint on Sep 09, 2018, 7:59 pm
As infered, being reminded where straight ahead is can only be good. ::)
My car feels around 10% in comparison, which i prefer.
Title: Re: Lift engine.
Post by: Ian Brooks on Sep 09, 2018, 11:45 pm
23% is advised by Barry "The Grand Master" Palmer. I have come to accept that I only disagree with Barry when I still have something to learn.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 11, 2018, 3:51 pm
Iím just happy if the rudders make the craft go in the rough direction I want to go.
As for self cantering I have arms that can do that.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 18, 2018, 6:08 pm
Itís alive.
https://youtu.be/GRwRNVZQNT8 (https://youtu.be/GRwRNVZQNT8)
Title: Re: Lift engine.
Post by: Philip on Sep 18, 2018, 6:41 pm
That sounds familiar :) , should work well. BTW with that shaped duct gives some very interesting airflow patterns.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 19, 2018, 8:19 am
As long as it works I donít care.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 26, 2018, 7:48 am
Bugger.
2 new pulse pumps original and a new mikuni cast outboard in the 16hp Briggs and it still wonít get fuel to the carb on full chat. (No blocked pipes and breather working).
Gravity feed it and no problem.
Didnít want to go down the electric pump but I fear I have no option.
Unless Iím missing something.
Title: Re: Lift engine.
Post by: Philip on Sep 26, 2018, 8:05 am
You've got a leak somewhere? Is the pump mounted as close as possible to the engine?
Title: Re: Lift engine.
Post by: John Robertson on Sep 26, 2018, 9:50 am
Lift height is next to nothing so that can't be the problem.  My guess would be the vacuum pipe to the pump - they need to be short and very stiff wall or the pipe "pulses" instead of the pump diaphragm.
Title: Re: Lift engine.
Post by: Warby on Sep 26, 2018, 11:19 am
Where is the pulse tube connected on engine? See photo of pulse tube connected to valve cover on Briggs engine.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 26, 2018, 7:55 pm
Checked all that. Short pipe. Ordered new pump. Engine was new old stock as was the outboard pump.
Ordered a facet pump and a new pulse pump.
Title: Re: Lift engine.
Post by: rossfloyd on Sep 26, 2018, 8:58 pm
I had hells own trouble after a rebuild ...until I found that I had connected the pipes the wrong way - very red face.


Previously I actually changed Britannia's entire lift engine because of this problem - I couldn't find the trouble until long afterwards - a tiny split on the side of the pulse tube - after a few minutes at full power it couldn't quite give enough fuel.  Caused a few very nasty moments off St Thomas' Head. 


I tried an elec pump and went back to pulse.  My back ups are the engine primers - KISS comes to mind !
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 27, 2018, 5:15 pm
Sorted the problem.
This is a brand new engine. I put the original pump back on the craft and still didnít work. So I changed the original Briggs fuel filter for a new filter (bought ten off eBay ages ago).
Works a treat now. No issues and I now have a new unused facet pump for the box a bits.
Title: Re: Lift engine.
Post by: rossfloyd on Sep 27, 2018, 9:28 pm
I believe that Briggs had a batch of bad filters some time ago.  We had one on a mower that caused endless problems. Probably one of those ?
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Sep 28, 2018, 4:18 pm
Itís done the hard work is over.
Now itís a case of tweaking,checking pressures and possibly making the holes in the plenum bigger.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Dec 28, 2018, 7:48 pm
After bombing around at the hcbd hoverin trying my best to break the eagle 4.
I discovered the following.
Plenum pressure to is 80 thingies and the skirt pressure is 60 thingies.
Exhaust is too loud.
Lift engine needs an electric pump.
Blades need a tweak to get the max revs down from 9500 to 8000
Lift duct need cutting so the bottom edge is at the same level as the blades
Trailer needs work.
So all in all a fantastic result.
Title: Re: Lift engine.
Post by: Philip on Dec 28, 2018, 10:05 pm
Often thought about fitting an electric fuel pump when I had that setup, nevet bothered as the pulse pump never failed.
Title: Re: Lift engine.
Post by: Eric Yeoman on Dec 29, 2018, 11:01 am

Lift duct need cutting so the bottom edge is at the same level as the blades


Why? My lift ducts are a bit deeper than blade trailing edge, 25mm ?, Just askin'  :)
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Jan 01, 2019, 12:07 pm
The Space below the blades quite tight. Also should allow the air to distribute better. I could be wrong and Iím sure someone will advise me if Iím right or wrong.
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Jan 01, 2019, 12:10 pm
Often thought about fitting an electric fuel pump when I had that setup, nevet bothered as the pulse pump never failed.
Not sure yet think might need a better fuel filter. The inline one is vertical so there is a air in it. May get a subaru filter like I have on the bmw.
See pic.

Title: Re: Lift engine.
Post by: Ian Brooks on Jan 01, 2019, 4:47 pm
Ideally a fuel filter with a water trap, about 15 quid from eBay
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Jan 02, 2019, 6:13 pm
Ordered 2. Front and back.
Title: Re: Lift engine.
Post by: Philip on Jan 02, 2019, 6:35 pm
Commonly known in the trade as a "522 with water trap" :)
Title: Re: Lift engine.
Post by: Al on Jan 02, 2019, 7:41 pm
Thanks for reminding me Gary, I've just ordered a pair for the TS3  ;D .  Just need an engine to connect up to the rear one  ???

Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Feb 03, 2019, 6:29 pm
Exhaust butchered and packed
Title: Re: Lift engine.
Post by: Gary Firth (Gazza) on Feb 06, 2019, 2:34 pm
https://youtu.be/2K_aZfy8weU (https://youtu.be/2K_aZfy8weU)