Mercury 20HP Efi - Smoke on the water

[Brerabit]

Anybody out there with a Mercury 20 Efi or Mariner?

One of the reasons for buying this engine was that it could be stored/transported vertically. By that I don’t mean standing up but with the tiller up and the prop down rather than on it’s side which makes for easy loading/unloading and takes up much less space in the boot. The boot has a level floor.

My trips so far have required me to load the car a day or two before I’m going to use the boat and I’ve then found that it takes four or five pulls to start and then for a few seconds there’s some blue smoke - oil presumably. After that, no problems at all.

After my latest trip It was the next day before I got the motor out but I then let it stand for a couple of hours before I started it for flushing - no smoke.

I can only assume that the two hour wait in the upright position gave any oil that had seeped past the rings into the combustion chambers, a chance to drain back.

I can live with this quirk as transporting it on it’s side would give me significant problems with loading but I wondered if anyone else was experiencing the same and wondered whether it was something I should be concerned about?

[chris moody]

Have you checked the oil level with the dipstick?

[ChrisParish]

My old 9.9 mariner can be transported like that and would exhibit the same symptoms if I allowed the gearbox to get higher than the powerhead at any point. It’s also worth thinking about how movement of the car affects the movement of oil in the engine - for example, if you have the powerhead towards the front of the car and the prop towards the rear then oil will move during prolonged or sharp braking. It is even worse if you place the motor laterally across the back of the car as the forces encountered while navigating roundabouts can be quite high.
I found the best solution was to position it with the gearbox towards the front of the car and with a wooden block under the back of the powerhead to raise it.
I know that’s not an option in your car, as we discussed it at length on Monday, but other people may find this useful.

I wonder if you could make a sled to hold the engine the other way up (transom clamp down) as it would be if it was mounted on the back of the boat?

[Brerabit]

I wonder if you could make a sled to hold the engine the other way up (transom clamp down) as it would be if it was mounted on the back of the boat?

I think the sled idea may have possibilities. It would then put the combustion chambers at the top. If I move the trim peg to 6, the clamp is at a useful half-way angle to secure it both for initial attachment out of the car and then when the board’s horizontal it’ll also help secure it in transit with maybe the gearbox strapped in a yolk.

As far as the manual recommendations go the following is food for thought. Before I chose the Mercury, I was considering the Suzuki but they recommend against storing the engine prop up, tiller down. When I asked one of their customer support people why, I was told it was because of the risk of water collecting behind the prop, freezing and cracking the casting. When I explained that this was purely for transit and for a max of 48hrs in my car he told me there would be no problem. Mercury may have the same concerns about frost damage.

You raise an interesting point @chris moody. I checked the oil and it was slightly high - only a couple of millimetres over the top mark - but that's now after a few blue smoke episodes. It may have been over-filled but perhaps it's now nearly burnt off.

[harrison]

Despite what it says in the operating manual don’t think I’d ever transport our Mariner 20 efi rear face down. Not surprised your burning off oil as the crankcase is higher than the cylinder head in this orientation...what would you expect.
Don’t know whether this will do any long term damage, after all no different to popping some oil down the bores for winterising. Personally would rather know if my motor was burning oil due to wear rather than seeping past the rings due to improper transport.

Transport ours on the recommended port side and with power head elevated on a castored dolly to assist sliding into car.

[Brerabit]

Not surprised your burning off oil as the crankcase is higher than the cylinder head in this orientation...what would you expect.

Cut me a little slack here
When I bought the motor as a total newbie, Mercury told me verbally and in print, that the motor could be transported face down - as advertised (on it’s side is not do-able for me). They even went to the trouble of designing cast lugs/feet into the casing to both the face and port side to indicate the only two manufacturers approved orientations.
So I think it is reasonable to ‘expect’ it to be ok.

Since fitting the tacho I’m now a little more familiar with how the powerhead is configured and I too am surprised, in view of the layout, that this is recommended - but recommended it is…

However, I am going to investigate the sled suggestion from @ChrisParish which could work well if I have the headroom.

[ChrisParish]

@harrison if the manufacturer recommends that position for transit (and they do) then why should we question that? I don’t know about you, but I don’t know what internal baffles etc are in the engine.
I do recall that if I let the gear case get higher than the power head, even for a moment, then I would get a smokey start.
If the oil is over full, even slightly, then that could go some way to explaining why you get the smokey start.

Four strokes and quiet and fuel efficient - but they can be a royal pain in the arse.

@Brerabit I think the only hurdle you have is getting it through the comparatively low opening in the boot; you have loads of headroom inside the car - it’s getting it in which is tricky.

[harrison]

Cut me a little slack here

Ha! Ha! Chill out guys.

Well in fairness I only responded, as an owner of exactly the same motor, to your question on transporting arse end down and oil leakage. Apologies if it’s not the answer you hoped to hear.

I acknowledge Mercury state, perhaps wrongly, it can be transported that way, but considering the orientation of the cylinder head/crankcase it looks inherently wrong to me. So wrong that I would never even consider trying it...so thank you for proving my reservations.

If your happy to accept some oil burning on startup that’s fine by me...I’d just recommend keeping the power head elevated as high as possible.

When you look at the lugs on the rear of the motor, they are so close together, making standing a very precarious balancing operation. To me they look more like protection mouldings for the hood clasp.

Bit close together for balancing on methinks

I think manufacturers are increasingly under pressure now to provide motors able to be stored/transported on multiple sides. Perhaps some of the advertising claims are a little optimistic at the moment. Might be worth mentioning this to Barrus for their take on this, particularly if it was a feature relevant to your purchase.

More importantly, when are we going to see how the Voliare performs against these pesky T38’s.

[chris moody]

We have already tested the T38 and Volaire head to head last Monday @harrison

[sonny1]

i missed those results then, so pray tell what happened