My VG30-Powered Samurai

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iniazy
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Re: My VG30-Powered Samurai

Post by iniazy »

Hmmm

Weird thing is, all cylinders passed compression test quite well. All were around 160-175 PSI. I expected them to fail.

How on earth could that oil come on my spark plugs?
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okayfine
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Re: My VG30-Powered Samurai

Post by okayfine »

Proper oiling will still mask poorly-seated rings by taking up the space between the ring and the bore. Oil through the valve guides. Those are the two most common. Did you notice any smoke out the exhaust?

Pressurizing the cylinder at TDC should give you audible clues where the problem exists. Technically you don't need a leak-down gauge setup for that. Get each cylinder to TDC and thread in your compression tester without the gauge. Hook it up to good line pressure and start listening for where the air is coming out. Not coming out? That cylinder is sealing well.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
goichi1
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Re: My VG30-Powered Samurai

Post by goichi1 »

If I were you, I would look into the harness, if all was well before, and then you install a new harness, that could be the culprit. Maybe something is not getting power that it should or something is not grounded properly?? The main thing is not to get frustrated and start tearing into the motor before you check every little thing first and don't be disappointed in yourself, you just built a pretty cool truck that has a few issues, nothing you can't figure out with some troubleshooting, and if it is internal in the motor, you already know how to get it out and tear it down and put it back together....not a big deal.
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Re: My VG30-Powered Samurai

Post by goichi1 »

just looking back in your thread, did you properly offset the ring gaps when you installed the rings on the pistons? just checking....
iniazy
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Re: My VG30-Powered Samurai

Post by iniazy »

Considering the plugs are already fouled and wet, I completely ruled out the harness since. I did check everything electrical, which isn't much considering it is a carburetted engine.
goichi1 wrote:just looking back in your thread, did you properly offset the ring gaps when you installed the rings on the pistons? just checking....
No I didn't :shock:

I thought since it is a kit specifically made for this engine I thought it should be all perfect. I didn't have fealer gauges and got lazy.

I wonder if the engine breaks in properly and the rings fully seated that it might get better? Just holding on to some hope :(
goichi1
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Re: My VG30-Powered Samurai

Post by goichi1 »

well, I'm not sure if it will be ok or not, I guess only time will tell. Usually you take a ring and slide it in the cylinder and check the ring gap before you install it on a piston. This is just a way to make sure they fit the cylinder correctly. A manual should tell you the tolerance on ring end gap. Then once you check that, you install them on the piston, then offset or space out the gaps to different positions on the piston so that all your gaps don't line up. If they all line up, oil can get by much easier than if they are staggered about the piston. Especially the bottom oil scraping rings, that's the three piece ring set that all goes on the lower groove on the piston.
Last edited by goichi1 on 09 May 2013 08:24, edited 1 time in total.
goichi1
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Re: My VG30-Powered Samurai

Post by goichi1 »

Also, reading back to when you took the block to a machine shop, they said it didn't need anything, I would have been a little skeptical on this, most always you should hone the cylinder if you are installing new rings. This will allow for proper seating of the rings. You should also ridge ream the cylinders too. This will greatly reduce the chance of breaking a ring during piston installation. now, I am not an engine builder, I have only done a few, the latest was a toyota 22R that was a quick rings and bearings change. but it ran fine when I was done.
iniazy
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Re: My VG30-Powered Samurai

Post by iniazy »

goichi1 wrote:Also, reading back to when you took the block to a machine shop, they said it didn't need anything, I would have been a little skeptical on this, most always you should hone the cylinder if you are installing new rings. This will allow for proper seating of the rings. You should also ridge ream the cylinders too. This will greatly reduce the chance of breaking a ring during piston installation. now, I am not an engine builder, I have only done a few, the latest was a toyota 22R that was a quick rings and bearings change. but it ran fine when I was done.
That's what I'm mostly suspecting. I did install the rings at different angles (clocked them), but many told me it was a mistake not honing the cylinders. Also, I did not check the block for cracks, and it was a very old engine.

I'll wait and try to break the engine in and see how things will go. I probably will have to rebuild it again.

I put in some new plugs and the engine is smooth again now. Probably a matter of time before it fouls again.
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Re: My VG30-Powered Samurai

Post by goichi1 »

Yea, honing is easy too, you can def so that yourself, just buy a hone and stick it in a drill and run it in and out of the cylinder till you get a nice consistant cross hatch. It doesn't take long if the cylinders are clean to begin with. The ridge reamer takes that edge off the top of the cylinder wall, this makes it really easy for the pistons to slide in with the spring compressor. Around here we can rent the tools at local auto parts stores, pretty cheap. but I'm sure you can buy them at affordable prices.
iniazy
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Re: My VG30-Powered Samurai

Post by iniazy »

Ok I finally got a chance to take my Zuki for a spin. Finally got my wiring harness issues sorted out, put back my dash and steering and everything is working well now.

But seems the engine is still not getting enough cooling. There is no loss in coolant, no leaks anywhere, so it is either the Radiator is not big enough, or the electric fan is not blowing enough air.

I am suspecting it is just the fan. A friend of mine has the same engine I've got on a Suzuki, and has even a smaller radiator, but no cooling problems at all.

My fan is a Flex-a-lite fan with only 1250 CFM. So I'm going to order a 2500 or 3000 CFM fan. I might have to give up on power steering though, because there will not be enough room for the PS drive pulley, and it most likely will have to go, sadly.

My radiator core dimensions are 15" wide x 16 1/2" wide, the Trail Tough radiator. I'm thinking of this fan, but seems a bit too big:
http://automotive.flex-a-lite.com/elect ... c-fan.html
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okayfine
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Re: My VG30-Powered Samurai

Post by okayfine »

I had fan issue. The radiator would cool fine, but once it got hot enough the fan couldn't move enough air to bring the temps back down. I switched from a 10" electric fan to the pump-mounted fan and it ran just a touch too cool. I didn't have space for a bigger fan.

How is your fan controlled? Google says it's ~91°F at peak, with a low of only 80 or so. That's enough temp if you don't have a for-sure cooling system.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
iniazy
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Re: My VG30-Powered Samurai

Post by iniazy »

okayfine wrote:I had fan issue. The radiator would cool fine, but once it got hot enough the fan couldn't move enough air to bring the temps back down. I switched from a 10" electric fan to the pump-mounted fan and it ran just a touch too cool. I didn't have space for a bigger fan.

How is your fan controlled? Google says it's ~91°F at peak, with a low of only 80 or so. That's enough temp if you don't have a for-sure cooling system.
I've got a temperature switch fitted to one of the custom radiator pipes that activates the electric fan at 85 degrees Celsius and switches off at 80. When the fan starts, it doesn't switch off and coolant temperature keeps rising slowly. So I had to stop testing the car.

I have absolutely no room for a pump mounted fan. Way too tight in there. I just placed an order for a Zergo fan 2750 CFM 14"x14 1/2. I hope this will solve my problem. Just concerned about that it doesn't have a shroud that will cover the radiator cooling core.

Edit: Hold on a sec! Are you saying 91°F peak? Is that F or C? 91°F is very cold the engine thermostat opens up at around 75°C, that's 167°F!
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okayfine
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Re: My VG30-Powered Samurai

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iniazy wrote:Edit: Hold on a sec! Are you saying 91°F peak? Is that F or C? 91°F is very cold the engine thermostat opens up at around 75°C, that's 167°F!
I was referring to ambient temperatures outside.

Most electric fans 510ers use don't have a full radiator shroud. Given the size of your new fan compared to the size of your radiator, I'm not sure a shroud would make all that much difference. One thing you should take a look at is to seal any gaps between the front of the radiator and the panel it bolts to, to ensure all the air goes THROUGH the radiator, and not around it.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
iniazy
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Re: My VG30-Powered Samurai

Post by iniazy »

okayfine wrote:
iniazy wrote:Edit: Hold on a sec! Are you saying 91°F peak? Is that F or C? 91°F is very cold the engine thermostat opens up at around 75°C, that's 167°F!
I was referring to ambient temperatures outside.

Most electric fans 510ers use don't have a full radiator shroud. Given the size of your new fan compared to the size of your radiator, I'm not sure a shroud would make all that much difference. One thing you should take a look at is to seal any gaps between the front of the radiator and the panel it bolts to, to ensure all the air goes THROUGH the radiator, and not around it.
Got it. Thanks. That's good to know.

I just ordered this fan:
http://www.zirgo.com/catalog/products/a ... ooling-Fan

Image

They claim it blows 2785 CFM, and it is very compact, will fit my radiator. That's really really impressive, considering the size of the fan. I hope it really does blow as much air as they claim.
iniazy
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Re: My VG30-Powered Samurai

Post by iniazy »

Finally received the fan. Here's the fan I ordered:
Image

It's got a massive motor, really big and took so much room. Bye bye power steering :(

I hope I don't have to do without the A/C compressor too.

Image

It almost touches the water pump screws. If this doesn't do it, then I'll have to replace the radiator, I think.
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