Skip Navigation Links
Setup
New Post
Search
Forum Home
Home
Decoder

Original Message
RE: 69 Merc 390 Vacuum Advance
By Royce P - 06/11/2006 11:16:31 AM; IP 66.42.239.4
Actually there is something else that is part of the system, the thermostatically controlled vacuum valve screwed into your thermostat housing. Unported vacuum goes to the thermostat housing and it is routed to the distributor port in different ways depending on whether the engine is hot or cold. I don't have the vacuum schematic for your vehicle or I would tell you what the proper connections are.

The schematic is in the factory shop manual. The intent is to retard the spark when water temperature goes over about 210 degrees which has the effect of raising the idle RPM helping to cool the engine because the fan and water pump would spin faster at idle speed.

Royce
This thread, so far...
Skip Navigation Links.
Collapse <a href=../ForumFE/reply.aspx?ID=27606&Reply=27606><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor27606" onclick="return false;">69 Merc 390 Vacuum Advance</a>&nbsp;-- <font color=#0000ff>AJ, <i>06/11/2006</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=27606', contentMargin: 60, icon: $('anchor27606') }); </script>  69 Merc 390 Vacuum Advance -- AJ, 06/11/2006
Collapse <b>RE: 69 Merc 390 Vacuum Advance</b>&nbsp;-- <font color=#0000ff>Royce P, <i>06/11/2006</i></font>RE: 69 Merc 390 Vacuum Advance -- Royce P, 06/11/2006
Collapse <a href=../ForumFE/reply.aspx?ID=27614&Reply=27606><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor27614" onclick="return false;">RE: 69 Merc 390 Vacuum Advance</a>&nbsp;-- <font color=#0000ff>AJ, <i>06/11/2006</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=27614', contentMargin: 60, icon: $('anchor27614') }); </script>  RE: 69 Merc 390 Vacuum Advance -- AJ, 06/11/2006
Collapse <a href=../ForumFE/reply.aspx?ID=27619&Reply=27606><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor27619" onclick="return false;">I'll bet this is more 'distributor advance' info than you wanted...</a>&nbsp;-- <font color=#0000ff>Mr F, <i>06/11/2006</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=27619', contentMargin: 60, icon: $('anchor27619') }); </script>  I'll bet this is more 'distributor advance' info than you wanted... -- Mr F, 06/11/2006
 RE: I'll bet this is more 'distributor advance' info than you wanted... -- AJ, 06/12/2006
 390 2v A/T: basic advance = 6° @550 rpm; 28-38° @2K rpm [n/m] -- Mr F, 06/13/2006
Collapse <a href=../ForumFE/reply.aspx?ID=27631&Reply=27606><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor27631" onclick="return false;">Yes - pull 'em to set timing. Read these related posts (& threads)...</a>&nbsp;-- <font color=#0000ff>Mr F, <i>06/13/2006</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=27631', contentMargin: 60, icon: $('anchor27631') }); </script>  Yes - pull 'em to set timing. Read these related posts (& threads)... -- Mr F, 06/13/2006
Collapse <a href=../ForumFE/reply.aspx?ID=27637&Reply=27606><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor27637" onclick="return false;">RE: Yes - pull 'em to set timing. Read these related posts (& threads)...</a>&nbsp;-- <font color=#0000ff>AJ, <i>06/13/2006</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=27637', contentMargin: 60, icon: $('anchor27637') }); </script>  RE: Yes - pull 'em to set timing. Read these related posts (& threads)... -- AJ, 06/13/2006
 Best advance varies w/ compression, state-of-tune, fuel type, etc. [n/m] -- Mr F, 06/13/2006
 Here's another 'advance' thread that might come in handy... -- Mr F, 06/13/2006
Post A Response
Name:
Email Address:
Subject:
Post:
Upload Image:
Human Check:   Enter the code 202471746 in the box