50:1 2 stroke in a 4 stroke engine?

We have a selection of 2 stroke engines and 1x4 stroke engines.

Apparently someone, who shall be nameless, not me, has attempted to run our 4 stroke on 2 stroke fuel. Not to sure the result but do I have to go to the fad of draining the engine or will reconnecting it to normal fuel be OK?
Depending on how much is in the tank, you can dilute with straight petrol and burn it or drain it, its only a litre or so!
The issue with burning it is that if you leave it in the carb for a while, the petrol evaps leaving oil to congeal, the jets can get clogged, the jets in a two stroke are a touch bigger.
Plus oil in fuel weakens the mixture, ask bike racers with the new fangled 2T Yamaha twins back in the day. Put a bit extra oil in, and it weakened the mixture, causing them to seize on full chat!
 
My old Suffolk Colt 4T lawn mower ran for years on the left over two stroke mix-25:1 Castrol 'R' 40 and five star petrol from the racing two stroke bikes-it never oiled a plug, always started easily, just smoked a bit and smelled like Brands Hatch!
 
My old Suffolk Colt 4T lawn mower ran for years on the left over two stroke mix-25:1 Castrol 'R' 40 and five star petrol from the racing two stroke bikes-it never oiled a plug, always started easily, just smoked a bit and smelled like Brands Hatch!
An old, side valve? Low compression 4 stroke with a carb used to passing vast quantities of fuel through enormous jets?
My little Honda gennie at home is similar!
 
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I remember the old engines as well, your anecdote doesn’t chime with what I remember! Most had a coil in the inlet manifold which had diesel dribbled on them to produce vapour or even flames!
I had a vague memory of diesel being actually burned (having been electrically ignited/vapourised) in the inlet manifold on some engines, and tried to look it up recently (can't remember why).

Could find no documented trace of it, but the idea really confused the AI on my browser.
 
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I remember the old engines as well, your anecdote doesn’t chime with what I remember! Most had a coil in the inlet manifold which had diesel dribbled on them to produce vapour or even flames!

The Glow plug as you talk about was not a standard fitting to trucks in those days ... to boat engines and cars - yes ... or to battle tanks with Perkins engines.

My 4-107 has the glow element in intake ... and you press the 12v button till you see a wisp of smoke out of air filter OR you hear the POP of the diesel igniting ... then hit the starter.

Bedford TK's ... TD's ... Ford D600, D800, D1000's etc etc all had governor over-ride to throw gobs of diesel in ... its why they smoked so much when started .. and going up hills before the pull knob was moved in the cab. Some moved the pull-knob to outside the cab and under the rear cab bodywork.
If they had Glow element - what use would it be to get uphills ?????
 
I had a vague memory of diesel being actually burned (having been electrically ignited/vapourised) in the inlet manifold on some engines, and tried to look it up recently (can't remember why).

Could find no documented trace of it, but the idea really confused the AI on my browser.

Perkins 4-99 ... 4-107 ... 4-108 ... all had optional Glow Element in the air intake below the filter. It had a bimetal valve affair that allowed diesel to ooze from a small tank above it (usually only a few2 100 ml's size) .. the diesel oozed onto the red hot 12v element. Perkins were not the only engines to have this.

Google Search

The later evolution of course is the modern Glowplug version that most diesel engines now have ...

The big Perkins engines in Battle Tanks used to have similar idea - but far more 'oomph' of course.
 
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Perkins 4-99 ... 4-107 ... 4-108 ... all had optional Glow Element in the air intake below the filter. It had a bimetal valve affair that allowed diesel to ooze from a small tank above it (usually only a few2 100 ml's size) .. the diesel oozed onto the red hot 12v element. Perkins were not the only engines to have this.

Google Search

The later evolution of course is the modern Glowplug version that most diesel engines now have ...

The big Perkins engines in Battle Tanks used to have similar idea - but far more 'oomph' of course.
Thanks. Interesting

I suspect I was wondering about possibly improvising something for my Yanmar 1GM10, which has no glow plug.

Maybe gas rather than electrical heating, to aid hand starting
 
The Glow plug as you talk about was not a standard fitting to trucks in those days ... to boat engines and cars - yes ... or to battle tanks with Perkins engines.

My 4-107 has the glow element in intake ... and you press the 12v button till you see a wisp of smoke out of air filter OR you hear the POP of the diesel igniting ... then hit the starter.

Bedford TK's ... TD's ... Ford D600, D800, D1000's etc etc all had governor over-ride to throw gobs of diesel in ... its why they smoked so much when started .. and going up hills before the pull knob was moved in the cab. Some moved the pull-knob to outside the cab and under the rear cab bodywork.
If they had Glow element - what use would it be to get uphills ?????
Good old Perkins...

Edit: The two Perkins on our boat start very easily even at -1c, they start almost instantaneous
 
It starts a small fire in the air intake? Really? 😬😱

If you were to keep the button pressed - yes it will .....

The manual tells you to press for about 10 secs until you hear a POP or see white wisp of smoke from the air intake ... because the air intake is restricted - the resulting flame is actually tiny or non existent - its hot diesel fumes ...
Remove the filter and open up the intake pipe and yes - you can easily get what you see in the video. But that is extreme and video creator must have been holding the button longer than necessary.
 
The Glow plug as you talk about was not a standard fitting to trucks in those days ... to boat engines and cars - yes ... or to battle tanks with Perkins engines.

My 4-107 has the glow element in intake ... and you press the 12v button till you see a wisp of smoke out of air filter OR you hear the POP of the diesel igniting ... then hit the starter.

Bedford TK's ... TD's ... Ford D600, D800, D1000's etc etc all had governor over-ride to throw gobs of diesel in ... its why they smoked so much when started .. and going up hills before the pull knob was moved in the cab. Some moved the pull-knob to outside the cab and under the rear cab bodywork.
If they had Glow element - what use would it be to get uphills ?????
That was the push button on the pump for cold start, old age dear boy!
 
Monday the local marine engineer is coming to service the two Perkins diseasels on the boat, I don't think I will ask him to demonstrate the above video, any way my engines are a bit different than the ones in the video, I hope no smoke or flame issues forth from the turbos :oops:

There is a H and HS on the ignition switches but it is on a different side than what is in the user manual and service manuals
 
Monday the local marine engineer is coming to service the two Perkins diseasels on the boat, I don't think I will ask him to demonstrate the above video, any way my engines are a bit different than the ones in the video, I hope no smoke or flame issues forth from the turbos :oops:

There is a H and HS on the ignition switches but it is on a different side than what is in the user manual and service manuals
Depends on the age of them
 
If the engine is in good order it will start easily, no heating required.

I often started our 1GM 10 by hand.
There's a thread on it. Doesnt seem to be the general experience, but perhaps engines generally aren't in "good order".

Mine probably isn't, but/and/for example, it doesn't seem to have a starting handle
 
That was the push button on the pump for cold start, old age dear boy!

As a teenager - I actually drove Bedford TK 330's .. 380's ... Ford D800 and D1000's ...... and all of them had a PULL button that did exactly what I described earlier.
The TK's had the button by your left hip next to the key ... the D series Fords had it next to the gearlever. Then when the Truck Company got its later Leyland powered Bedfords and new D series - the PULL button was located under the rear cab body preventing the driver from using it while driving. It was NOT on the pump ... it was a PULL button with cable.
 
Monday the local marine engineer is coming to service the two Perkins diseasels on the boat, I don't think I will ask him to demonstrate the above video, any way my engines are a bit different than the ones in the video, I hope no smoke or flame issues forth from the turbos :oops:

There is a H and HS on the ignition switches but it is on a different side than what is in the user manual and service manuals
I added a short length of stiff pipe to my Cold Start on my 4-107 .... holds about a teaspoon of diesel. On my previous 4-99 - I used a small plastic medicine bottle, but found that the bi-metal valve in the plug dribbled all the time.

But its rarely used ... in fact I cannot remember the last time I used it.

It sounds scary to have a flame - but according to engineers and Perkins - its kinder on the engine than throwing gobs of Ether at it !!
 
The old Bedfords my father had required a healthy dose of ether to get them to fire up, the BMC FG with the Perkins 6.354 in it was an instant starter never required any help summer or winter. and now I have the same engines in the boat although the ones in the boat are turbo charged.
On the Bedfords there was a kind of pump handle for cold starting it was just to the left of the steering wheel, don't really remember much about them as I didn't drive them much, The BMC, Morris and Austin trucks I drove a fair bit, but mainly the Morris, it had a 4.something litre 6cyl petrol engine as did the Austin, they were ex army 1ton 4x4.
The BMC was a crewcab with 11 seats, 2 up front and 9 in 3 rows in the back, then a flatbed behind that, it was ex-Electricity Board and used for transporting wooden power/telephone poles, it was about as long as a single decker bus and governed to 50mph. I remember when one of the guys at the garage opened the engine cover when we first got the truck and his eyes lighting up and saying "Ohhh a Perkins, this is a good one"
 
The old Bedfords my father had required a healthy dose of ether to get them to fire up, the BMC FG with the Perkins 6.354 in it was an instant starter never required any help summer or winter. and now I have the same engines in the boat although the ones in the boat are turbo charged.
On the Bedfords there was a kind of pump handle for cold starting it was just to the left of the steering wheel, don't really remember much about them as I didn't drive them much, The BMC, Morris and Austin trucks I drove a fair bit, but mainly the Morris, it had a 4.something litre 6cyl petrol engine as did the Austin, they were ex army 1ton 4x4.
The BMC was a crewcab with 11 seats, 2 up front and 9 in 3 rows in the back, then a flatbed behind that, it was ex-Electricity Board and used for transporting wooden power/telephone poles, it was about as long as a single decker bus and governed to 50mph. I remember when one of the guys at the garage opened the engine cover when we first got the truck and his eyes lighting up and saying "Ohhh a Perkins, this is a good one"

No idea what Bedford that was - but the TK's .. TD's never had such pump handle ...

They had a simple pull knob next to the key in the back panel to drivers left. There were three items there .... Cold Start Pull knob .... Knob that screwed out that adjusted low speed rpm so you could set crawler speed in 1st gear ... and the 'start' key.
 
.....The TK's had the button by your left hip next to the key ... the D series Fords had it next to the gearlever. Then when the Truck Company got its later Leyland powered Bedfords and new D series - the PULL button was located under the rear cab body preventing the driver from using it while driving. It was NOT on the pump ... it was a PULL button with cable.

It was a legal thing that the excess fuel button couldn't be operated from inside the cab.

The pump things you mention were an option, pumping ether for cold starts.
 
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