Honda Grom banner

1 - 20 of 20 Posts

·
Registered
Joined
·
60 Posts
Discussion Starter #1
Good day fellow gromers,

Just installed a 57mm bore, 24/28 head, 28mm TB, high cam, crankshaft and an oil cooler.

So I was running in this few days with a short distance run around my house. Nothing weird happened.

Last night I plan of going further just to run in my bike. Was doing 6-7k RPM maintaining my speed at 70kmh. At some point I went higher to nearing 8k rpm for a while and hit 90kmh on forth gear.

At the rest stop I notice my engine oil is leaking from my piston block. Dripping a little on my exhaust pipe header and smoke coming out from the drip and heat. I couldn't pin point it is from the gasket of connecting my piston block to my crank shaft or my head gasket.

That point I was 50km from home. Considering it was a minor leak I ride home with 5-6k RPM with 50-60km/h.

Reaching home I don't notice any dripping on my header exhaust but there's some oil hanging below my piston block, it wasn't that much compare to what I see at the rest stop.

I did filled in 1.3L of engine oil as I had install an oil cooler from the beginning. I have a crankcase breather hose on as well.

May I know how can I fix this? Do I need to reduce compression for the combustion chamber? Or just search for a better gasket?

Hope you guys can share me some of your experience.

Thanks.
 

·
Registered
Joined
·
1,030 Posts
First, clean off the excess oil from the suspect areas. Needs to be dry and oil free.

Did you torque the head in steps? (9, 12, 18 for instance)

Retorque your head. Do not loosen it, just make sure that the torque value is correct. 18 FT# for the 4 on the head & the cam chain side, 6 after having tightened the 4 head bolts.

Check your tappet clearances after retorqing the head. Make sure the tappet covers are tight & the orings are in good shape.

GO out & ride a short distance and see if you can find any oil seepage. If you do find seepage, it is time for new gaskets.

Good luck!
 

·
Registered
Joined
·
8,323 Posts
Just re-check everything that is torque down ok and also one major change I would make if you are using a stock airbox and your breather hose from the crank is attached to it, I would remove that hose and attach that hose to a oil catch can.

You do not want any oil mist going back into your engine via the intake.

Check that your air filter is not damp with engine oil, if it is than you will need a oil catch can. A good oil catch can will also help with the crank case pressure in your engine and reduce engine internal heat.

Sometimes oil comes from oil that dripped off the spout hole when you installed the new oil into your motor.

Good luck and ride safe
 

·
Registered
Joined
·
60 Posts
Discussion Starter #4 (Edited)
First, clean off the excess oil from the suspect areas. Needs to be dry and oil free.

Did you torque the head in steps? (9, 12, 18 for instance)

Retorque your head. Do not loosen it, just make sure that the torque value is correct. 18 FT# for the 4 on the head & the cam chain side, 6 after having tightened the 4 head bolts.

Check your tappet clearances after retorqing the head. Make sure the tappet covers are tight & the orings are in good shape.

GO out & ride a short distance and see if you can find any oil seepage. If you do find seepage, it is time for new gaskets.

Good luck!
Sure thanks for sharing. But is there any chance of compression being to high therefore temperature is way too high to handle with higher pressure?

I dont have a temperature gauge tho ;/.

If I'm not mistaken, I'm currently using a copper head gasket. Will aluminum gasket works better?

Just re-check everything that is torque down ok and also one major change I would make if you are using a stock airbox and your breather hose from the crank is attached to it, I would remove that hose and attach that hose to a oil catch can.

You do not want any oil mist going back into your engine via the intake.

Check that your air filter is not damp with engine oil, if it is than you will need a oil catch can. A good oil catch can will also help with the crank case pressure in your engine and reduce engine internal heat.

Sometimes oil comes from oil that dripped off the spout hole when you installed the new oil into your motor.

Good luck and ride safe
I had my airbox removed due to my new throttle body does not fit the stock air hose. Therefore I change the air hose with an airfilter which look like a mushroom.

I've check the stock breather hose, there's no leakage there. Only oil seen under the piston block.
 

·
Registered
Joined
·
8,323 Posts
Only oil seen under the piston block.

check and make sure your oil temp sensor is torque down to spec, the one on the left lower side of your cylinder.

your copper head gasket is ok, the gasket for the cylinder to crank almost never leaks if installed properly.

By the way where is the breather hose attached to besides the crank case, where is the other end going to?

Also check your oil drain plug to make sure it is to torque spec and also that you did put the crush washer back on that plug/bolt
 

·
Registered
Joined
·
60 Posts
Discussion Starter #6
Only oil seen under the piston block.

check and make sure your oil temp sensor is torque down to spec, the one on the left lower side of your cylinder.

your copper head gasket is ok, the gasket for the cylinder to crank almost never leaks if installed properly.

By the way where is the breather hose attached to besides the crank case, where is the other end going to?

Also check your oil drain plug to make sure it is to torque spec and also that you did put the crush washer back on that plug/bolt
Noted sir..

As for the stock breather hose which attached to the airbox previously, I just left it hanging as I never see anything came out from it. So it is just hanging there without the airbox.

PS, I am using my stock oil pump. Things like super oil pump is hard to get in my country. I'm living close to Thailand and I found none of those. I got my stuff there they told me I don't need it.




Another question, does oil cooler gets hot when it is functioning? Mine doesn't.
 

·
Registered
Joined
·
8,323 Posts
As for the stock breather hose which attached to the airbox previously, I just left it hanging as I never see anything came out from it. So it is just hanging there without the airbox.


put a tiny filter unit on the end of the hanging hose just to keep bugs and sand and such from being sucked into the engine crank case
 

·
Registered
Joined
·
865 Posts
There is much good general information and advice being dispensed.....but......the OP has a oil leak.

The source/location of that oil leakage must first be determined in order for a repair to then be made. I would clean the outside of the engine, add more oil, and start running the motor until the leak re-appears.
 

·
Registered
Joined
·
1,030 Posts
Originally Posted by WV_Grom
Check your tappet clearances after retorqing the head.




Why would you do that? I suspect you dealt with too much old american iron lol
Never had a Harley in my life. By choice, of course.

IF the head was torqued to a lesser value than needed, when the correct value is applied, this will change the valve clearance.
 

·
Registered
Joined
·
28 Posts
"As for the stock breather hose which attached to the airbox previously, I just left it hanging as I never see anything came out from it. So it is just hanging there without the airbox."


If the stock breather hose was left off, it could blow oil onto the engine and and appear as a leak.

I forgot to attach mine once. I was looking for a leak for weeks until I removed the plastics and noticed the hose was disconnected. Reconnected the hose and never had the issue again.
 

·
Registered
Joined
·
8,323 Posts
"As for the stock breather hose which attached to the airbox previously, I just left it hanging as I never see anything came out from it. So it is just hanging there without the airbox."


If the stock breather hose was left off, it could blow oil onto the engine and and appear as a leak.

I forgot to attach mine once. I was looking for a leak for weeks until I removed the plastics and noticed the hose was disconnected. Reconnected the hose and never had the issue again.
yep oil mist comes out of the crank case vent port, just put a white cloth on the open part of the hose and zip tie it down and go ride around for a mile and check the cloth it will be oil soaked.
 

·
Registered
Joined
·
60 Posts
Discussion Starter #13
Have not change the gasket and I put a small oil catch can attached to my crankcase breather.

Took it out for a spin last night to see if it leak from oil catch can but found it was still from gasket. Nothing from crank case breather hose.

I can confirm it doesn't leak if I open 20-30 percent of my throttle. Once I went WOT it leaks more regardless of speed and tested in WOT to 5-7k RPM before I changed gear.


Do note that I've scan all the other areas, there's no oil leak or trace except for this part.
 

Attachments

·
Registered
Joined
·
720 Posts
Originally Posted by WV_Grom
Check your tappet clearances after retorqing the head.






Never had a Harley in my life. By choice, of course.

IF the head was torqued to a lesser value than needed, when the correct value is applied, this will change the valve clearance.
Piston to valve clearance theoretically but you'll rip out the studs before having problems. I don't see how valve lash would be affected.
 

·
Registered
Joined
·
17 Posts
Did you confirm that the two dowel pins in the cylinder head are in place and that the head gasket was put on correctly? Remove head and redo the work. You may need to use some copper based sealant on the head gasket this time.
 

·
Registered
Joined
·
1,030 Posts
Piston to valve clearance theoretically but you'll rip out the studs before having problems. I don't see how valve lash would be affected.
After dropping 2 tabs of Goofy, and thinking of this issue, you are correct David. I was visualizing, for some unknown reason, a push rod, silly me, eh? I should have known better.

Regardless, a valve clearance check is never a bad thing...
 

·
Registered
Joined
·
60 Posts
Discussion Starter #17
Update: suspect the surface of my block and head might not be even which causes the leak. I will send it for skimming soon. Also I tested the compression is at least 200 psi.

Which causes really high temp where I recorded on my phone connected to apitect ecu via Bluetooth. Not sure how accurate is the reading it shows 130celcius and that's maximum cap.

Currently porting the head chamber trying to achieve 160psi.

Anyone has any opinion please do share.
 

·
Registered
Joined
·
8,323 Posts
Update: suspect the surface of my block and head might not be even which causes the leak. I will send it for skimming soon. Also I tested the compression is at least 200 psi.

Which causes really high temp where I recorded on my phone connected to apitect ecu via Bluetooth. Not sure how accurate is the reading it shows 130celcius and that's maximum cap.

Currently porting the head chamber trying to achieve 160psi.

Anyone has any opinion please do share.
take a mechanic straight edge metal ruler and do a X measurement of the head to see if you see any gaps under the head.

As far as the groms crank case mating to the cylinder sleeve the gasket should take care of any thing that might leak. Check the top of the cylinder doing the X measurement as on the head.

 

·
Registered
Joined
·
60 Posts
Discussion Starter #19
Update: suspect the surface of my block and head might not be even which causes the leak. I will send it for skimming soon. Also I tested the compression is at least 200 psi.

Which causes really high temp where I recorded on my phone connected to apitect ecu via Bluetooth. Not sure how accurate is the reading it shows 130celcius and that's maximum cap.

Currently porting the head chamber trying to achieve 160psi.

Anyone has any opinion please do share.
take a mechanic straight edge metal ruler and do a X measurement of the head to see if you see any gaps under the head.

As far as the groms crank case mating to the cylinder sleeve the gasket should take care of any thing that might leak. Check the top of the cylinder doing the X measurement as on the head.

I did some flat surface treatment. Now still leaks but very minor compare to before. It seems like the engine oil sips through a little bit.

Another minor leak the valve cap. Using the one from Morin oil cooler. I've just drain the engine oil and refill it to 1 litre. Previously was definitely overfilled by 100 to 150ml. Gonna test it out when I have time to see if the leak does reduce.


Anyway I reduced the compression psi to 160. Bike runs better. Temp still goes up to 126 celcius max wot. Just ordered my self a takegawa pump oil I hope it doesn't cause more leakage as I think the pressure of pumping the oil is stronger.

will slowly run in my bike till 1000km and go for a dyno after this.

Lastly, thanks for replying Cisco.
 

·
Registered
Joined
·
26 Posts
The Takegawa and Kitaco pumps are high volume not high pressure, they pump the engine oil around faster.
 
1 - 20 of 20 Posts
Top