Gutless Stroker - JeepForum.com
 2Likes
Reply
 
LinkBack Thread Tools
post #1 of 25 Old 10-09-2017, 07:58 PM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Gutless Stroker

For a little background I built the stroker 3 years ago then I bought a house and had my first kid so long story short I just got it up and running after some wiring issues.

I used a 4.0 block and connecting rods with a 4.2 crank,hesco rvob6 cam, hesco FPR, 30lb/hr injectors, a 62mm throttle body, 7120 port/polished head. I can?t for the life of me remember what pistons I went with.. but I know I ordered a set of KB944-60 but they didn?t work for some reason and my machine shop ordered a similar set that would. I also can?t remeber what valve springs I used but I talked to hesco and ordered what they recommended for there cam. When I built the motor I followed the medium buck 4.7 build sheet from this site but it has changed since I built my motor. http://www.jeep4.0performance.4mg.com/stroker.html

Now that you know what?s done to the motor here?s my problem..... it will fire right up but sounds really rough at idle and has no power. I checked for misifires and found that I can pull the spark plug wires or fuel injector plug on cylinders 3 and 4 without any change. Then I checked for spark and power to the injectors and I have both. Next I did a compression check on cyl. 3,4,5 and all were close to 180psi (cold).

I?m not sure if I need to maybe advance timing or maybe the injector timing is off but there is something definitely wrong. I have an air fuel gauge and it?s running around 14.5-15.5 with the FPR set at 47psi.

Hopefully you guys can help me get this figured out. I would really appreciate it!


88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
Sponsored Links
Advertisement
 
post #2 of 25 Old 10-10-2017, 07:45 AM
gotswap
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2013
Location: Peyton
Posts: 978
If you pull the plugs on the impacted cylinders and ground them, do you get spark? That would at least help determine if you have a spark or fuel issue
gotswap is offline  
post #3 of 25 Old 10-10-2017, 08:31 AM
cyoos
Registered User
1992 YJ Wrangler 
 
Join Date: May 2008
Location: Wichita
Posts: 1,243
There's always the possibility that your cam is one tooth off. It will start but it will run pretty rough. I have no idea how I know this, but...uhmmm...well, yeah...I do. LOL

4.6L/AX15/OME/1" booms in back/8.8-4.10-LSD/XJ D30 in work/32" Falken Wildpeak AT's

Last edited by cyoos; 10-10-2017 at 08:31 AM. Reason: spelling correction
cyoos is offline  
 
post #4 of 25 Old 10-10-2017, 09:01 AM
shaggyjim
Web Wheeler
 
shaggyjim's Avatar
1992 YJ Wrangler 
 
Join Date: Nov 2008
Location: Grand Junction
Posts: 1,750
You have power to the injectors but is the injector actually firing off?

Jim...

"That's more fun than watching a hippie get mauled by a bear!"
shaggyjim is offline  
post #5 of 25 Old 10-10-2017, 10:57 AM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Quote:
Originally Posted by shaggyjim View Post
You have power to the injectors but is the injector actually firing off?
I just assumed they are firing. They are brand new injectors. I?ll put a stethoscope on them tonight and see if I can hear them fire.

88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
post #6 of 25 Old 10-10-2017, 10:59 AM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Quote:
Originally Posted by gotswap View Post
If you pull the plugs on the impacted cylinders and ground them, do you get spark? That would at least help determine if you have a spark or fuel issue
I have spark to the plugs and power to my injectors. My injectors are new so I assume they are firing but I?m going to double check tonight.

88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
post #7 of 25 Old 10-10-2017, 11:02 AM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Quote:
Originally Posted by cyoos View Post
There's always the possibility that your cam is one tooth off. It will start but it will run pretty rough. I have no idea how I know this, but...uhmmm...well, yeah...I do. LOL
Do you mean engine timing or ignition timing?

I degreed the cam when I put it in and double checked it before I closed everything up but that doesn?t mean I did it right haha if I don?t find anything else I will pull the motor back apart and check it again.

As for ignition timing I?ve set the distributor 1 tooth retarted and 1 tooth advanced of where it is now. But that was about a year ago so I?m going to check it again tonight.

88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
post #8 of 25 Old 10-10-2017, 02:49 PM
shaggyjim
Web Wheeler
 
shaggyjim's Avatar
1992 YJ Wrangler 
 
Join Date: Nov 2008
Location: Grand Junction
Posts: 1,750
Quote:
Originally Posted by youngjeepr View Post
I just assumed they are firing. They are brand new injectors. I?ll put a stethoscope on them tonight and see if I can hear them fire.
It might be just as easy to swap them to cylinders you know are running and see if the problems follow them. My first thought is that they corroded over in storage and wont open. My second thought and its a longshot is that if you have fuel and spark at the dead cylinders but the engine shows no change when they are deactivated I wonder if you wiped out some cam lobes from the long storage. Hopefully its just a timing issue.

Jim...

"That's more fun than watching a hippie get mauled by a bear!"
shaggyjim is offline  
post #9 of 25 Old 10-10-2017, 03:20 PM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Quote:
Originally Posted by shaggyjim View Post
Quote:
Originally Posted by youngjeepr View Post
I just assumed they are firing. They are brand new injectors. I?ll put a stethoscope on them tonight and see if I can hear them fire.
It might be just as easy to swap them to cylinders you know are running and see if the problems follow them. My first thought is that they corroded over in storage and wont open. My second thought and its a longshot is that if you have fuel and spark at the dead cylinders but the engine shows no change when they are deactivated I wonder if you wiped out some cam lobes from the long storage. Hopefully its just a timing issue.
I?ll swap the injectors and see what happens. I don?t think I have flattened cam lobes... the motor only has maybe an hour of run time on top of the 30 min cam breakin.. but who knows maybe I did. I?ll throw my dial indicator on a push rod and check the lift. Any idea how to check duration?

88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
post #10 of 25 Old 10-10-2017, 03:36 PM
shaggyjim
Web Wheeler
 
shaggyjim's Avatar
1992 YJ Wrangler 
 
Join Date: Nov 2008
Location: Grand Junction
Posts: 1,750
Like I said it was an outside chance with the cam. Did it run well when you did the cam brake in? Also when did you do the brake in? When it was built? Dumb question but you did set the timing with a timing light right?

Jim...

"That's more fun than watching a hippie get mauled by a bear!"
shaggyjim is offline  
post #11 of 25 Old 10-10-2017, 04:27 PM
cyoos
Registered User
1992 YJ Wrangler 
 
Join Date: May 2008
Location: Wichita
Posts: 1,243
Quote:
Originally Posted by youngjeepr View Post

Now that you know what?s done to the motor here?s my problem..... it will fire right up but sounds really rough at idle and has no power. I checked for misifires and found that I can pull the spark plug wires or fuel injector plug on cylinders 3 and 4 without any change.
Disregard what I said about the cam. I was trying to think and read at the same time and it didn't work out too well. After rereading it, it sounds like @gotswap and @shaggyjim are on the right track.

4.6L/AX15/OME/1" booms in back/8.8-4.10-LSD/XJ D30 in work/32" Falken Wildpeak AT's
cyoos is offline  
post #12 of 25 Old 10-10-2017, 04:46 PM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Quote:
Originally Posted by shaggyjim View Post
Like I said it was an outside chance with the cam. Did it run well when you did the cam brake in? Also when did you do the brake in? When it was built? Dumb question but you did set the timing with a timing light right?
I did the break in earlier this year probably around March. I had a pretty bad leak in my fuel tank so I didn?t run it longer than the 30 min cam break in time at 2k RPM. So I?m not sure how it ran at idle. It sounds smooth at above 1300RPM ish. I?ll take a video of it when I get time in the next day or 2.

Ignition timing is set by the ECM on the 4.0 and can?t be mechanically adjusted unless you cut the mounting point off the distributor housing. I havnt cut it off yet or checked the timing with my timing light. Just lined up the rotor in the dist. With number 1 plug while number 1 cyl. was at TDC on the compression stroke.

I figured I would get it running decent then fine tune it by mechanically adjusting the timing if needed.

I?m going to double check my timing aswell tonight when I get home from work.

88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
post #13 of 25 Old 10-10-2017, 07:06 PM
shaggyjim
Web Wheeler
 
shaggyjim's Avatar
1992 YJ Wrangler 
 
Join Date: Nov 2008
Location: Grand Junction
Posts: 1,750
Quote:
Originally Posted by youngjeepr View Post
I did the break in earlier this year probably around March. I had a pretty bad leak in my fuel tank so I didn?t run it longer than the 30 min cam break in time at 2k RPM. So I?m not sure how it ran at idle. It sounds smooth at above 1300RPM ish. I?ll take a video of it when I get time in the next day or 2.

Ignition timing is set by the ECM on the 4.0 and can?t be mechanically adjusted unless you cut the mounting point off the distributor housing. I havnt cut it off yet or checked the timing with my timing light. Just lined up the rotor in the dist. With number 1 plug while number 1 cyl. was at TDC on the compression stroke.

I figured I would get it running decent then fine tune it by mechanically adjusting the timing if needed.

I?m going to double check my timing aswell tonight when I get home from work.

Well how bout that. I learn something new everyday.

Jim...

"That's more fun than watching a hippie get mauled by a bear!"
shaggyjim is offline  
post #14 of 25 Old 10-10-2017, 10:27 PM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Well I didn?t get to the injectors tonight but I did check my timing. It was retarted pretty far so I moved it a tooth advanced but it wouldn?t start... Then I moved it a tooth back and it barely ran so I tried moving it back to the original spot and couldn?t find the sweet spot. So tomorrow after work I?ll put #1cyl at TDC and drop the dist. back in the right spot but this time I?ll cut the mounting point off so I can manually time the motor with a vacuum gauge.

88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
post #15 of 25 Old 10-11-2017, 06:13 AM Thread Starter
youngjeepr
Registered User
1988 YJ Wrangler 
 
Join Date: Aug 2009
Location: layton UT
Posts: 2,545
Well I just found out that indexing the dist. Doesn?t adjust ignition timing it only adjusts injector timing.
gotswap likes this.

88 YJ- 4.7l stroker, AW4, SOA, 8.8, hp D30 powertrax no slip,3" front stretch with waggy springs, stock replacement springs in the rear, 35/12.5 r15 goodyear kevlars


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
youngjeepr is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com 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 e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 Off
Pingbacks are On
Refbacks are On

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