Need second opinion- engine block - JeepForum.com
 1Likes
  • 1 Post By Goatboy4570
 
LinkBack Thread Tools
post #1 of 6 Old 07-09-2020, 08:11 AM Thread Starter
Chelu55
Registered User
 
Chelu55's Avatar
 
Join Date: Jul 2019
Posts: 17
Need second opinion- engine block

Seeking some advice on which direction I should go. I was planning on doing an AMC 304 rebuild. After looking over the block, I noticed a deep gash at the corner of one of the cylinders. It’s pretty large, about 1/32 deep. I don’t know the history of the engine, so I don’t know how it ran, but the PO already got it bored 30 over, purchased pistons to match, new bearings, balanced, etc.

My question: given the depth and location, should I cut my losses and find a better block? Any insight on what would be required to “fix” and est cost? I’m rebuilding on a budget, so cost is a major factor. Like most, I also don’t want to invest time and $ on something that will cause problems post-transplant.

Attached Thumbnails
1D9F9E40-3749-4909-AED7-4EF051FF9323_1594303491081.jpg   A4695915-F1DB-40E7-98D5-3710C1AC0F48_1594303518717.jpg  
Chelu55 is offline  
Sponsored Links
Advertisement
 
post #2 of 6 Old 07-11-2020, 12:52 PM
RedBolide
Registered User
 
Join Date: Dec 2019
Location: Atlanta
Posts: 58
Since nobody else has chimed in yet, I'll offer my two cents. That gash doesn't look terrible, but it looks big enough to be problematic. You could probably get it all back together and it would seal enough to get you down the road, but I'd expect you to get a noticable loss of compression in that cylinder. It might be tough to find a cheap block to replace it, but I'd recommend you start searching. That gash is enough to scare me away. Perhaps someone else has a different option.

'03 Wrangler Sport / '98 Grand Cherokee Laredo / '90 Comanche Eliminator
RedBolide is offline  
post #3 of 6 Old 07-11-2020, 01:36 PM
222Doc
Registered User
 
222Doc's Avatar
2012 JK Wrangler 
 
Join Date: Sep 2011
Location: Lake Havasu City
Posts: 9,412
Garage
dont think it would change the CR enough that could be measured. Bush fix is with care smooth it off. Real fix is to take some off the deck. I would go with the bush fix, Though looking at the rest of the deck it looks kinda funky too like this block was handled by monkeys.

decking will change CR. Not even sure how much deck you have to play with on that block, how much can be done with out making other issues like how the manifold may fit the valley push rod lengths etc... What is the Cr now and how much deck needs to be squared up, taken down. carb engine you wont want that CR to high.

Home of the Parker Desert Splash

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.
222Doc is offline  
 
post #4 of 6 Old 07-11-2020, 06:50 PM
Goatboy4570
Registered User
 
Goatboy4570's Avatar
1983 CJ7 
 
Join Date: Jul 2014
Location: nanaimo
Posts: 52
Nik in cylinder

I would lay a head gasket on there and see where it sets, the gasket bore is usually 0.100" bigger than the bore itself, its possible the gasket will sit outside this damaged area.
Goatboy4570 is offline  
post #5 of 6 Old 07-13-2020, 09:48 PM Thread Starter
Chelu55
Registered User
 
Chelu55's Avatar
 
Join Date: Jul 2019
Posts: 17
Thanks for responding. I appreciate the honest feedback. I’m on the fence on whether I should use the block. I really don’t think it’s worth spending the extra cash to fix it or rolling the dice. If I need to spend extra to fix it, I might as well find a suitable 360 to rebuild. Open to any additional thoughts. Thanks again.
Chelu55 is offline  
post #6 of 6 Old 07-14-2020, 12:38 PM
Goatboy4570
Registered User
 
Goatboy4570's Avatar
1983 CJ7 
 
Join Date: Jul 2014
Location: nanaimo
Posts: 52
Bigger head gasket on smaller bore

If it was me i wouldn't even hesitate for a split second throwing a larger bore 243 or 360 head gasket on there and never giving it another thought.

The bigger bore gasket will sit outside the damage, it will have a little bit of dead space and drop compression a 1/10 or 2 of a point but all that is insignificant when the alternative is to discard an otherwize perfectly useable block.

Seems to me the 304 has the potential to be a fuel efficient little V8, i'd run a Q-jet or a 650 street demon and an RV cam at around 212-214 @ 0.050 duration, headers, and a nice valve grind.
Chelu55 likes this.
Goatboy4570 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











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