PRE IGNITION FORD 250 crossflow

Gotcha! :LOL: Architects are harder targets to hit. :eek:

More seriously, I tell people to pour the water down the carby at a "piddle", to convey the rate/amount. Most can relate to that pretty well. ;) How literally they interpret that instruction has now been given the all clear by yourself.

Cheers, Adam.
 
I dunno if taking a slash down the carby would hurt the combustion chambers, but I'm sure the other stuff in it might.. stuff like minerals and salts. Unless you like to drink lots of beer while working on the car. Then it'd probably be pretty clear of those impurities :D
 
I just solved a pinging problem on the ZC (250 Crossflow) - turns out the coil lead was faulty right near the coil - lead broken under the right angle boot and arcing in there
Once I found that and replaced it, I could bring the initial advance up about 5 degrees...
It also stopped the strange loss of power every now and then
And makes it start heaps better...
 
Ull neva guess what happened... i was driving back to sydney from the cental coast and i copped a lot of rain closs to floods.... and i drove through a huge puddle.... the carby drank so much water that it wouldnt start at all... i was stranded... it cleared up a bit and then u could tell there was a whole lot of water in their still... it cleared up eventually... i looked at my carby and its got black stuff... would the best thing to do just carby clean it... it seems fine right now.. i drove all the way back to syd and had no problems... wills like normal.. maybe a tiny tiny bit sluggish... what should i do??? do u think that by chance this was a good enough water treatment? would it hurt to give it another one?
 
Large amount of water = quenching of combustion and cooling of cylinders. Motor cools unevenly from sudden stop, therefore hard to start. Sounds like normal engine behaviour under the circumstances. Don't be too worried, as long as no strange noises are eminating from under the hood that weren't there before. If the sysmptoms have disappeared, good, else try another gentle water treatment, ie don't drive through flood waters. If symptoms persist or come back, maybe it not entirely a carbon build-up problem.

Teddy :)

Sorry I haven't posted for a day or two, laid up by a head cold for the last ocuple of days :(
 
I have just done a click carby clean to clean up all that black shit that was from all the flooding water.. the carby was pissing it all out....

I did a slow dribble of water... u could hear the water burning/steaming.. did it for about 5-10 minutes... i hopped in the car and i could notice a smoother throttle.. the car turned off without a worry.. i turned it on and off a couple of times it was fine...

This could just me my imagination.. it could be the same and nothing could of happened.... i guess i just have to wait and see... i also have put in an additive in the petrol.. a fuel system cleaner that is suppose to last for 5000kms.. or whatever and cleans excess carbon.. i thought id give it a try...

What ive tend to notice is... and i forgot to mention this before.... When i drive the car like a granny... i think it tends to build up excess carbon.. i guess this is because the throttle tends to get caught down low as mentioned before... because of this constant problem.. this could be what is gathering the carbon.... but when i drive it and press on it a bit... i cant help but think im clearing it out a bit.. because it blows out black smoke and after a couple of times the black smoke is reduced... not as much?

I will get back to you and let you know how the water treatment works out. Thanks again.. sorry for the late reply i just havent had a chance to do this water treatment.
 
I have done a couple of short trips.. and bad new is that i just got back and as i got home i had the car idling for a while and when i went to turn it off it didnt turn off to smoothly.. just a quick Kick

Someone mentioned to me because ive got such a big cam that this will be close to impossible to prevent
 
Yeh its definately doing it still...

Another query.. What do you think about the new Optimax Extreme? its got ethanol in it... but its 100 octane.. and if u throw in an octane booster?

Do u think the ethanol would cause any damage?
 
Ethanol wont do any damage to the motor, in fact, the ethanol is what helps get the octane up to those levels. For most motors running on petrol, there is no problem with ethanol in the fuel providing it doesn't go past about 10%. If one of the major oil companies is going to put their neck out and put ethanol in their fuel you can bet your bottom dollar that it will be well controlled and it wont exceed the 10% mark. Where ethanol may bite a few unwary customers is its effects on the rubber and plastic components in the fuel system. It is a much better solvent than petrol and can 'soften' some rubber and plastics. That said, most modern rubber and plactic components should be able to stand up to it. If you use it, just keep in mind those effects and do a small check every so often. One other effect is that ethanol can help clean out a lot of junk from the fuel system, so keep a close eye on the fuel filter, you might need to replace it sooner than you anticipated.

My general view is ethanol is a good thing, just be aware of some of the pit falls I mentioned.

Regards,

Teddy :)
 
In the Feb '06 issue of car craft there is a small section on using E85 which is an 85% ethanol blend available in most parts of both south and north america. They suggested that whilest it has a lower BTU rating than regular unleaded it has a much higher octane rating around 129 RON. The same as race gas but at have the price. Allowing the use of a lot more compression and more aggressive engine tune without detonation.

They claimed the only drawbacks as a slight loss (10%) in fuel economy and the need for a few minor adjustments to the carburretor idle circuit. As far as corrosion is concerned ethanol is no where near as corrosive as methanol.

I think that at only 10% ethanol, which is all they are allowed to sell in australia you shouldn't have any problems
 
Any other suggestions on pre ignition or detonation???

Thanks for all ur help as well! :) much appreciated
 
I have tried something different... i put in a NULON PRo Strength octane booster in the tank, then i have put in the new Optimax Extreme 100 octane with 5% ethanol..... The i have never felt the car run smoother.. and its reduced the bogging down low in the carby and most of all soon as i have put this in and run it with this petrol there has been no pre ignition? It has been turning off smoothly... once the petrol runs out im going to go back to 98 octane and see how it goes... i will let you know what happens...

Can someone explain to me what does this all mean? how an affect of 2 octane can make a difference? (well im not sure if thats totally true.. this may have helped in combination with the water treatment to clean out all the excess carbon...)

Thanks
 
Could just mean that your set-up requires, or prefers, the highest octane you can give it. If I remember correctly you are running a high compression, higher than standard anyway, which generally means you need a higher octane petrol. I know some new higher performance motors are running high compression, but they can get away with it because they have the anti-knock sensors that can retard the ignition enough and the flow into the cyclinders creates much more turbulance and mixing/swirl than a lot of the older motors. So when you raise an older motor to such high compression, you can only compensate with the octane rating of the petrol you use. (there are other factors that effect how a motor behaves with different compression ratios, they were the first two that came to mind, and I'm not that knowledgeable about it!!)

This really leaves you a couple of choices. Stay with the highest octane you can get your hands on, or run a water injection unit to handle the lower octane fuels. My preference would be the water injection as it'll likely save you a bit in the long run. 100 octane fuel can't be cheap, can't get it here in the country anyway. Water injection will probably loose you a couple of neddy's at the rear wheels, but will save your motor from detonating itself to kingdom come if you get a bad batch of fuel somewhere along the line. It'll also mean you can run normal premium from anywhere you might travel to, as the really high octane isn't available everywhere you go. Also, if its set up in such a way that it can be turned off, you can always put a batch of 100 octane in whenever you feel like it. (or run 100 octane with the water and see how it behaves)

As I said a while ago, you'll be amazed at what you learn and dicover on the way to solving the problem...... :D

Regards,

Teddy :)
 
How do i go about a water injection system? How much am i looking at? Where do i get it from and how do you install it? How does it work?
 
HOw long is a piece of string?? :eek: In this instance there is a miriad of ways to install water injection. I've known of some which were cobbled together from a windscreen washer pump and some tubing, to commercial set-ups that have every bell and whistle imaginable. Really, it comes down to $$ as to what you end up with. Some systems will automatically come on as soon as the car starts, others will only come on (activated by pressure or microswitch) once the throttle is opened past a pre-determined level. Probably the best way to research the topic is to use the "search" function on this website as I'm sure its been discussed a number of times on the other forums. Punch in "water injection" into Google and you'll bring up a heap of hits, list goes on and on. Do a bit of research and see what might suit your set-up. One approach might be to put together a really cheap do-it-yourself setup initially to see if it helps your problems. If that works, you could then look at getting something a little more proffesional. It hink Holley does a water injection set-up, though I have no idea what it might cost. There are a lot of other sites on the web that can show you how to put together a water injection unit. Ultimately, a unit that can provide water in as fine a mist as possible would be best. Cheap set-ups merely pump a stream of water into the carby and rely on the high velocity air to break it into droplets. Look around and see what you can find. It really will depend on what you are prepared to put up with/do yourself/pay for.

Regards,

Teddy :)
 
So far so good...

I have run about 25 litres of 98 octane with no additive or octane boost there was no problem...

I then run a full tank of 100 octane with no additive or octane boost... i just finished that and once again i have had no problem.

I now am running 98 octane i just put a full tank in and im going to stick to that because of petrol prices they are terrible. Its Optimax 98 octane...

After this tank i will get back to you all and let you know if i have any problems or if it ever does it again. Thanks for all your time and replies...
 
TeddyXY71":1yprkfo3 said:
Water down the carby shouldn't do any harm to the motor or the carby, but again I stress that you do things in moderation. When I've done this on my old XY, I get the hose going at a very small continuous dribble, with the stream no thicker than, say, a drinking straw. But the motor has to be running, and like I said previously, you may need to manually rev the motor to keep the rev's up.

Now if this method clears up your problem, then you have a couple of possible scenarios to consider. Either the carbon had built up previously and now that its gone, the correct tune should maintain things and prevent it coming back. If the problem re-appears after some time, then you can probably assume carbon has built up again and just repeat the treatment OR as Addo mentioned, install a permanent water injection system to keep the carbon at bay permanently.

If the treatment doesn't get rid of the problem, it may not be a pre-ignition problem from carbon. As I think someone else mentioned on another related post, have you considered the possibility of this being detonation, rather than pre-ignition?? If it is detonation, then installing a permanent water injection should help in that department. Seeing as you're running 10.5:1 compression, detonation might be a possibility.

Another thought that just popped into my head...you said earlier that it still bogged down a bit even after changing from the 600 Holley to the 450... are you sure that the 450 isn't still too much carb? I know that a lot of other people are running 350 Holley's which gives them good drivability for their application. Think about what your normal rev range is for general driving conditions. Changing diff ratio will merely bring up the revs, thereby bringing the larger carb into its prefered operation range for air flow. You be the judge as to whether its cheaper to change a carb or change a gear ratio.

That'll give you a few things to think about, so I'll leave it there.

Regards,

Teddy :)
Click to expand...
The easiest way to do it is by using the vacuum line from the dizzy, it doesnt suck too fast, but keep the engine revving
 
Well its definately got something to do with the petrol. It doesnt like the 98 octane petrol... it has started to not want to switch off again. The 100 octane works well but its too expensive to run it... is there a cheaper way out of this? can i put some additive in or what petrol should i be running???

Keep in mind i have a 10.5:1 compresssion ratio..
 
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