PDA

View Full Version : Mercedes 300D conversion 2nd car



Fitian
28th February 2007, 10:40 PM
Hello fine people,

I'd like to share with you my 2nd car conversion.

This one is

- 300D 1980 1st car was 1981
- Two tank conversion like the first car
- Main tank is used for vegy oil in this car and I used a small start up tank at the boot with a blend of (20% ULP and 80% Vegy oil).

http://www.members.optusnet.com.au/~cncbrog/setupA.JPG

Another view



http://www.members.optusnet.com.au/~cncbrog/setupB.JPG

Startup tank

http://www.members.optusnet.com.au/~cncbrog/Start up tank.JPG

In this setup I have also connected the FPHE to the CAV filter then oil will come out of the CAV to the 1st coil heater then to the valve then to the 2nd coil heater and to the LP. This way the oil will get hot in the twin coil heater befor it goes to the engine meanwhile the FPHE will heat up more oil to replace what's in the CAV filter.

Before :
FPHE > 1st coil > CAV > Valve > 2nd coil > engine.
Now
FPHE > CAV > 1st coil > valve > 2nd coil > engine.

In the start up tank, I have fitted the clear fuel hoses through drilled holes and I inserted a rubber washer in the holes for a tigh fit to stop the hoses from being pulled out. I have also drilled a small hole in the drums cap and inserted a small tube from an empty pen to let some air into the tank also it stops the blend from being all over the boot when the tnak is full.

A part from the dramas I had with the faulty valve, This car is running like a dream with a good long range vegy tank approx. 70 L.

Any thoughts are welcomed.


Regards,

Fitian

W123 x 2
1st March 2007, 08:22 AM
Hi Fitian,

Nice one. That looks like a 20 litre start up tank that would take you 250km at a pinch ;)

Keeping the hose manufacturers in business too :p

cheers, Michael

David
4th March 2007, 04:04 PM
Hi Fitian,

I see that you have gone across " To the dark Side" and are using a bled. Excelent! I have created another "Risk taker ! I know you will not have any problems with it and you'll probably wish you had done it earlier.

Am I right in reading you are now using 3 heat exchangers?? Have you actually measured any output temps to see if you do need this many and they are making a difference?

I like how you set the plastic tank up! Very neat indeed.
I'm sitting here looking at it wondering though if I would myself prefer my current system where the hoses are in the lid allowing me to just swap the entire tank or would it be better to be filling one tank from another? I have to watch the dribbles when I pull my fuel lines out of the tank but I can also see dribbles and spills when refilling a tank. What to do?

Both seem to have their advantages and drawbacks but your tank certainly looks professional!

I'm starting my own conversion and ready to fit my home made heat exchanger. the first thing I have come up against is that on the heater outlet on the engine head seems to be a different size to that on the heater fitting on the firewall. The respective sizes seem to be 7/8 on the head and 5/8 on the heater connection. Are these the sizes of the fittings on your car? If so, did you use different size hose barbs on your HE or did you get around this some other way to fit one size hose?
I guess it would be too easy of they made all the fittings the same size :mad:

Nice job once again mate.

Fitian
4th March 2007, 11:56 PM
David,

Thank you for your kind words my friend.



Am I right in reading you are now using 3 heat exchangers?? Have you actually measured any output temps to see if you do need this many and they are making a difference?

I have used the same heat exchangers used in my first car. 20 FPHE and twin coil. Nothing extra.


I like how you set the plastic tank up! Very neat indeed.

Thanks heaps.




I'm sitting here looking at it wondering though if I would myself prefer my current system where the hoses are in the lid allowing me to just swap the entire tank or would it be better to be filling one tank from another? I have to watch the dribbles when I pull my fuel lines out of the tank but I can also see dribbles and spills when refilling a tank. What to do?


I have decided to go on with a fixed "small 15L" tank for start up on this car because I have seen how often I need to fill up my start up tank on the first car. I take around three month before I need to come near it. Now with the this start up tank I top it up once every 5 days going that is if I warm up the car with 2 Litres along the day which is plenty. You are more likely to dribble oils hear and there if you swap tanks - I fill up using a 5 L jerry can "coolant jerry can" and I never get any oil dribbling at all. I have also choosen to place it on the right side of the car in case my wife or myself wanted to fill up at the petrol station "50/50 blend" we do not have to remember which side has what.



I'm starting my own conversion and ready to fit my home made heat exchanger. the first thing I have come up against is that on the heater outlet on the engine head seems to be a different size to that on the heater fitting on the firewall. The respective sizes seem to be 7/8 on the head and 5/8 on the heater connection. Are these the sizes of the fittings on your car? If so, did you use different size hose barbs on your HE or did you get around this some other way to fit one size hose?

I had to face the same problem when I bought the twin coil heater. It comes with 1/5'' barbs for the coolant while the barbs in the rest of the fittings were all 5/8'' and like said 7/8 on the engine.

I bought two different fittings for the coolant on the FPHE 1/2'' at coolant entry and 5/8'' for the exit or return hose.
At the engine I bought one special hose from supercheap auto $11 that has two different ends one 7/8'' and the other end 5/8''.

To fit the oil heaters, I made a T with two 5/8'' barbs in line ends and one with 1/2'' to go to the twin coil. The 5/8'' ends - one is taking from the engine's special hose 5/8'' and the other one goes to the heater barb at the fire wall. the third barb is 1/2'' to go to the twin coil coolant entry. Other end of the twin coil 1/2'' goes to the FPHE 1/2'' barb.

The return coolant hose is 5/8'' and is going to same size so no worries there.

Of course it would have been great if they all come in one size but again there will be no thinking or a challenge ;) .



Thanks again for the your kind words my friend.

Cheers,

Fitian

David
5th March 2007, 01:03 PM
At the engine I bought one special hose from supercheap auto $11 that has two different ends one 7/8'' and the other end 5/8''.



Hi Fitian,
I was poking round the ( overpriced) hoses at supercheapo on Saturday looking for something like you describe. Do you have the tag with the hose number of know what the hose was originally to fit?

So far my soloution is to put a copper joiner ( yorkshire) fitting over the 3/4 pipe and hope that will pack it out close enough for a piece of 7/8" hose to be clamped to. I was also going to see how far I could pump the plain tube out with an expander but I think it wouldn't be enough and may make the tube too thin or be liable to crack.
The plug screwed into the head looks like it could be made any size so I can only assume they made it larger in order to make some $$ in spare parts down the track. :mad:

Fitian
5th March 2007, 04:37 PM
David,

I do not have the tag for this special hose. But I can buy it and list it on ebay for you to bid on :D .

I will get you one mate if you want to just let me know.

Cheers,

Fitian

Fitian
6th March 2007, 12:29 PM
Just a quick update ...

I forgot to mention that in this car I did not loop the return vegy line. I have sent it back to the tank to release any air in the system.

I do not see that the V80P20 blend is working well in cold mornings. some mornings the car won't start and I had to take the other one otherwise we are late for work. It take a few seconds then starts when it is warm enough say after 11 am. I have gone back to V50D50 and had no troubles in cold mornings.

It seems that the vegy blend with ULP is causing problems. Any thoughts?

Cheers

Fitian

W123 x 2
6th March 2007, 02:12 PM
Hi Fitian,

I had my first coldish start for the year with overnight air temp at 8 degrees C. Started up with one GP cycle and kicked in after 4 complete rotations at 7 am and 10 degrees C on V88P12 (approx). Car garaged but roller door open.

My girl is not in the best of shape needing new glow plugs and valve adjustments. Probably needs the injectors cleaned too :o

Could it be that the P20 is too much and not allowing compression ignition to occur at lower temps? Viscosity of V50D50 is greater from memory than V80P20 so it's not likely to be lack of flue flow.

cheers, Michael

Fitian
6th March 2007, 02:26 PM
I do not know Michael but it does not seem to work for me and many others.

If my car is happy with 50/50 then so be it. It is only for a start up anyway so I hardly use two litres a day in total.

Normally 300Ds are very forgiving though

Regards,

Fitian

Tony From West Oz
7th March 2007, 12:31 AM
Having 3 * 300Ds in our stable, I can point out some differences in the year models with regard to starting on veggie / veggie blends / biodiesel.
I will try to tabulate the starting performance on each fuel in the order above:

'78 OM617, series GPs (in '81 280E body)
100% Veggie starts fine after shutdown when hot, if allowed to sit >10 minutes needs GP for 5 seconds. No cold start possible on veggie.
Veggie / Biodiesel blends (50:50). As for 100% veggie.
100% biodiesel. GP 15 seconds when cold, starts 2nd revolution. Hot or warm, no GP needed.

'80 OM617 in '82 300D body.
100% veggie. Cold start. GP light goes out, wait 10 seconds, crank and it starts first revolution - needs fast idle to prevent stalling. Warm & Hot, starts without GP wait.
50:50 veggie / biodiesel. Normal GP wait (~5 sec) when cold, starts first revolution.
100% biodiesel - Normal GP wait (~5 sec) only when cold, starts first revolution.

'84 OM617 (Fatmobile)
100% veggie. Cold start. GP light goes out, wait 10 seconds, crank and it starts first revolution - needs fast idle to prevent stalling. Warm & Hot, starts without GP wait.
50:50 veggie / biodiesel. Normal GP wait (~5 sec) when cold, starts first revolution.
100% biodiesel - Normal GP wait (~5 sec) only when cold, starts first revolution.


Whether the starting differences for the pre- '80 OM617 is related to the GP style, or injector / IP issues is unknown.

I plan to perform compression testing on all 3 engines soon (month or months time - depending on other workload) and will post on the forum for comparison with others' OM617s

Regards,
Tony

Fitian
7th March 2007, 04:59 AM
Tony,

Have you ever tried ULP blend in any of you cars?

What do you think of ULP blend any way?

Cheers,

David
7th March 2007, 10:00 AM
I'm a bit surprised you are having trouble starting on a 20% blend Fitian. I have found that my car can be a little hard to start on 10% but seems to be OK at 15% and never had a problem at 20. I had a bit of trouble starting the last couple of mornings on 12% but I threw about 5Ml of Methanol down the intake and it fired right up in a few turns of the engine.

From experience and what I have read, I am thinking that the ambient air temp has more to do with starting than the fuel temp or the temp of the engine between cold and really cold. As you are just using blend for starting, maybe you could try going up to 25% petrol and see how that goes? In my experience more perol makes the car easier to start but does not run as well once it is hot which wouldn't be a concern in your case.

BTW, who are the many other people you are aware of that the blending is not working for? I haven't heard any of this so would be interested to find out who is having trouble and what their circumstances are.

Tony,
Thanks for posting that info, it gives me a great deal of reassurance!
I had heard other people saying they could cold start on veggie and was worried that my '78 would only do it just before the battery expired if at all. It is good to know that cars of similar vintage also have problemsand it is not just because my engine may be clapped out.
The temp has dropped these last couple of mornings here and the 12% blend I am using dosen't seem to be getting the job done in a very timely fashion either.

Whenever I start her from cold, I need to keep the foot well down for about 5-10 seconds or she will stall. Once Past that, it will idle quite happily with the idle controll turned well up untill the engine is warm where it can then be backed off.

I did start Helga this morning and ran the engine for only a few minutes to let my wife get her car out from behind. About 20 Minutes later when I came back to it, it fired first turn with about 10 sec on the glow plugs. It dosent seem to need much heat but some heat makes a big difference.

Fitian
7th March 2007, 07:58 PM
Hello David,

As you said at the end of your post. Last few mornings were colder than the usual. I almost drained the battary one morning and the car won't start. So I see no point be stuborn. I only need a thin fuel to start the car and run it for 15 min max. My friend Jack "my local mechanic" has got a ute and I told him about the V80P20 and supplied him with oil but he also had trouble starting in some mornings - His time worth more money than than a dollar or two of saving. Laurie also had some trouble with cold starting as well as leaking injectors after introducing ULP.

I guess every engine will react differently so if it works for you then it is great but it did not work for me. It was good to try though at least we are not in real winter.

I will stick to bio for start ups.

Have fun mate

Tony From West Oz
7th March 2007, 11:47 PM
Tony,

Have you ever tried ULP blend in any of you cars?

What do you think of ULP blend any way?

Cheers,

Fitian,
I do not have an opinion on ULP blends as I have not trialled them. I use only biodiesel as a blending agent (effectively "poor conversion biodiesel")
I have used ULP as a starting aid, pouring a little into the inlet manifold prior to cranking on a cold engine with veggie in the injectors.

I have also used WD40, CRC and other sprays of light oils, into the inlet manifold, to "start" diesels with non-functioning, or poorly functioning, injection systems.

Tony

W123 x 2
8th March 2007, 08:03 AM
Hi,

Check your manuals, apparently Mercedes Benz says adding 5% petrol to dino diesel in winter may be necessary (is permissible) to reduce viscosity to enable fuel flow and cold weather starts.

I'm assured this info is contained in the genuine MB workshop manual on disc for the W123 diesels; it doesn't get more authoritative than that!

Cheers, Michael

Lozzer
8th March 2007, 12:08 PM
"I'm assured this info is contained in the genuine MB workshop manual"

That's reassuring to hear Michael!
Laurie
PS Dont worry Fitian...still planning for two tank system. (with blend in startup tank of course)