Headers, Intake, & Exhaust Custom Exhaust? New Headers? Need Opinions on Intakes? Discuss making your ride breathe better here.

Changed lower intake gasket, now no compression

Old 01-20-2017, 01:25 PM
Starting Member
Thread Starter
Join Date: Jan 2017
Posts: 2
bblack13 is on a distinguished road
Default Changed lower intake gasket, now no compression

Hi everyone. First let me say, I have been using this forum for several years now to search for info and help regarding my blazer. You guys rock.

Hopefully this is in the right place. I've never posted on here before.

I have a 95 blazer. I had a few problems in October with starting on cold days. I replaced the battery and starter, which seemed to fix the problem. I had a fuel pump go out a week later, which we got changed. I also replaced my injector assembly last year.

My blazer was running great and starting up very quickly for about a month after the fuel pump was replaced. I had a lower intake gasket leak, and decided to replace it myself. IN order to get the gaskets replaced I had to remove the distributor. It is an older style with the vertical posts and caps.

After getting everything torqued back down (with a torque wrench) and getting the distributor lined up with my marks, I could not get the engine to start. It was crank but now start. I had spark for a while, but I had dry plugs. After several attempts to reset the timing we lost spark and still had dry plugs. Mechanic #1 said it was the coil pickup inside the distributor. We bought a whole new distributor, new cap and rotor. Then we started getting spark and flooded spark plugs, but still crank no start condition.

I have since taken it to the chevy dealership to reset the timing (timing chain is 2-3yrs old). They said they couldn't find compression on #1cyl, or various other cylinders that they tested. Mechanic #2 says he thinks it's valve and rocker related. He thought I mis-adjusted them. I never touched the rockers or valves. I pulled the valve covers off to replace the seals. I had everything covered with paper towels during cleaning.

What would cause a loss of compression on several cylinders after replacing a lower intake gasket? Both my dad and uncle think the timing chain broke on an off coincident. My dad thought the started didn't sound right. Mechanic #2 said he thought I over torqued the intake manifold bolts. I used a torque wrench on the lower intake bolts, and torqued them to spec in the tightening sequence specified by Haynes manual. The upper intake plenum I hand tightened.

We decided to tow the vehicle home and try to make a new plan, maybe even putting a used engine in. But I"m still interested to hear your suggestions. Thanks in advance
Old 01-20-2017, 02:44 PM
rexmburns's Avatar
Join Date: Sep 2011
Location: Northern VA
Posts: 4,379
rexmburns has a spectacular aura aboutrexmburns has a spectacular aura aboutrexmburns has a spectacular aura about

My money is on your distributor being installed incorrectly. It's very easy to install them 180 off or even just a single tooth off.
Old 01-20-2017, 03:47 PM
Starting Member
Thread Starter
Join Date: Jan 2017
Posts: 2
bblack13 is on a distinguished road

Thanks for the quick reply. I know there is/was a timing issue with the old and new distributor. The dealer mechanic (mechanic #2) tried to find tdc #1cyl on compression stroke and was unable to get the gauge to give a compression reading. He tried several other cylinders and could not get a compression reading for those either. So he was unable to reset the timing the easy way (without pulling more pieces off). But regardless of the timing, there is still no compression in at least 3cylinders.
Related Topics
Thread Starter
Last Post
Engine & Transmission
06-28-2016 01:13 PM
Engine & Transmission
04-22-2014 02:04 PM
Engine & Transmission
03-12-2013 11:01 AM
Engine & Transmission
07-03-2012 06:51 AM
2nd Gen S-series (1995-2005) Tech
03-07-2012 02:04 PM

Thread Tools
Search this Thread
Quick Reply: Changed lower intake gasket, now no compression

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.