07 Raptor 350 over heating - Yamaha ATV Forum
 
LinkBack Thread Tools Display Modes
post #1 of 6 Old 08-25-2017, 10:46 AM Thread Starter
Junior Member
 
MalcolmV8's Avatar
 
Join Date: Aug 2017
Posts: 15
07 Raptor 350 over heating

Hey Guys,

I picked up an 07 Raptor that had run low on oil and trashed the motor. So the kid repaired it with a big bore and stroker kit making it a 379 cc. When I went to pick it up it would not hardly run and he said it was because he hadn't re-jetted the carb for the additional CC.

Here's the new 07



I got it home and noticed it was running very lean as expected. I kept upping the jets, mostly the main jet till I pretty much had it maxed out but the quad started running decent. I took it out for a test drive (16 acres at a buddy's house) and noticed it was getting really hot. I was not hammering on it, just cruising around. We have several warrior/raptor 350s out there so I had a lot of references. I grabbed my IR temp gun and the others show approximately 240F on the front right side of the head. This 07 was showing more like 340+ and even 360F and I'd shut it down and just let it sit.


Out doing some testing



So at this point I'm thinking the quad is still running very lean. So I decided to put a wideband in instead of trying to read plugs and keep guessing because it wasn't tuning in like they normally do. Also installed a whole new exhaust since the stock one was trash.

Wideband installed


Almost immediately after that I notice the head gasket was blown. Ugg. I thought I saw it blow smoke when I went to look at it but then couldn't get it to replicate so thought I was going crazy but no it was blown lol.

So pulled it apart and got head to machine shop


Machine shop had to take off .004 to straighten head and had to order custom sized commetic MLS head gasket since it has an over size bore.

All back together. Now with the head gasket fixed I see it's pig rich. I had to jet it way back down to more expected jets. Turns out the blown head gasket was creating the super lean condition the whole time.

Heading out for another test drive.


Loan behold the dang thing still runs hot. How confusing. I know the A/F is spot on now due to the wideband yet in a few laps around the property I notice it's up to 365F + and you can smell burning. The engine eventually just shutdown from over heating. I let it sit and cool and confirmed it fired back up and was not completely seized.

Now I'm wondering about oil in this thing so I start googling and find how you can remove a bolt on the top of the head that opens up an oil port and confirm oil pressure. Sure enough I get nothing. So I pull the oil filter cover and oil filter itself and fire it up and not a drop comes out. Ugg so the dang oil pump has been trashed since the previous guy broke it and rebuilt the motor with the same old trashed oil pump.

Tear down again


Sure enough oil pump was completely trashed and locked up with metal shavings from the original motor failure. I removed it and got a new one in there.


So now I have oil pressure, verified on port. Air fuel ratio is in check, verified on wideband. Fins on engine are clear of dirt and have good access for air flow. Yet the dang thing still over heats like crazy. I'm out of ideas? What would still cause this thing to be getting so incredibly hot?

Any pointers or experience with over heating like this is greatly appreciated.

Thanks
Malcolm

07 Raptor 350
A few Warrior 350s
MalcolmV8 is offline  
Sponsored Links
Advertisement
 
post #2 of 6 Old 08-25-2017, 05:27 PM
Senior Member
 
Join Date: Feb 2015
Location: southern oregon
Posts: 1,880
Garage
did you inspect the prefilter screen on the drain plug, sometimes they can stay in the machine. i had one that was plugged and it got so hot it melted the stator wires on a rickystator. the only other thing i can think of is it has possibly been regeared to tall and you are having to stay to high in the rps to ride it. are you still getting smoke out of the breather tube? what are your head temps now. i have not had one in almost 2 years but 300 next to the pipe does not sound crazy hot. is the pipe glowing.
cory52000 is offline  
post #3 of 6 Old 08-25-2017, 06:09 PM Thread Starter
Junior Member
 
MalcolmV8's Avatar
 
Join Date: Aug 2017
Posts: 15
Quote:
Originally Posted by cory52000 View Post
did you inspect the prefilter screen on the drain plug, sometimes they can stay in the machine. i had one that was plugged and it got so hot it melted the stator wires on a rickystator. the only other thing i can think of is it has possibly been regeared to tall and you are having to stay to high in the rps to ride it. are you still getting smoke out of the breather tube? what are your head temps now. i have not had one in almost 2 years but 300 next to the pipe does not sound crazy hot. is the pipe glowing.
When I got it the drain plug was broke and the screen and spring where missing. I replaced all that but if the old one is jammed in somewhere I have no clue.
No smoke out the breather tube or exhaust even. It's around 365+ and it's on the right side of head. Exhaust is on left side of head, I know it's close but our other Warriors/Raptors run around 240 on the same spot of the head.
This one gets so hot you'll start smelling the oil burning and if you keep riding (as I did once) it eventually seizes up it gets so hot. Luckily the seize was not permanent but I probably took a good 10+ years service life off the motor lol.

My other thought is perhaps since the oil system is fixed now the problem is back to been lean. I'm wondering if the wideband needs special considerations for such a tiny pipe compare to a car's exhaust? I started reading plugs again and to me it looks lean as hell even though my wideband is telling me it's on the richer side. Confusing.

Exhaust pipe was not glowing. Brand new FMF which I think is stainless steel. Discoloration near the head but that should be normal.

07 Raptor 350
A few Warrior 350s
MalcolmV8 is offline  
Sponsored Links
Advertisement
 
post #4 of 6 Old 08-25-2017, 07:24 PM
Senior Member
 
Join Date: Feb 2015
Location: southern oregon
Posts: 1,880
Garage
i am way to old for the computer stuff but if that plug is not brown moving to black i would go back up what is your elevation and what main are you running. you seem very through but are you sure the timing is dead on some advance could cause the heating.
cory52000 is offline  
post #5 of 6 Old 08-26-2017, 03:23 PM Thread Starter
Junior Member
 
MalcolmV8's Avatar
 
Join Date: Aug 2017
Posts: 15
I agree, the wideband I don't think is working correctly in this small exhaust. I put in a new plug and ran it a while (let it cool etc.) and kept running it and it's staying clear and new looking. That's definitely lean. Now that I have oil working I'm going to go back to jetting by reading plugs and ditch this wideband.

I have not validated the timing. Good point there, overly advanced timing can heat it up too. I have the workshop manual for the quad, I'll read up on the specific procedure for timing on this motor and see where it's at. I appreciate the input.

07 Raptor 350
A few Warrior 350s
MalcolmV8 is offline  
post #6 of 6 Old 07-29-2019, 02:29 PM
Junior Member
 
Join Date: Jul 2019
Posts: 1
Check your timing. It could definitely be running hot if timing is off
Dmanindfw is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Yamaha ATV Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome